W 


'2H 


K) 


BULLETIN  No.  27.         SAN  FRANCISCO,  JANUARY,  1908. 


THE 

QUICKSLVER  RESOURCES 

OF  CALIFORNIA. 

(SECOND    EDITION.) 


ISSUED  BY 

THE  CALIFORNIA  STATE  MINING  BUREAU, 

FERRY  BUILDING,  SAN  FRANCISCO. 


UNDER  THE  DIRECTION  OF 

LEWIS  E.  AUBURY,        -         -        State  Mineralogist. 


SACRAMENTO. 

W.  W.  SHANNON.         -         -         -         SUPERINTENDENT  OF  STATE  PRINTING. 

1908. 
LIBRARY 

UNIVERSITY  OF  CAUFORNIA 
DAVIS 


LETTER  OF  TRANSMITTAL. 


To  Hon.  George  C.  Pardee,  Governor  of  the  State  of  Cali- 
fornia^ and  the  Honorable  the  Board  of  Trustees  of  the 
State  Mining  Burea^i : 

Gentlemen:  I  have  the  honor  to  transmit  the  results  of 
the  recent  work  of  the  State  Mining  Bureau  in  investigating 
the  Quicksilver  Resources  of  California,  and  which  are  embodied 
in  Bulletin  Xo.  27. 

This  is  the  third  of  a  series  of  bulletins,  issued  under  my 
direction,  on  special  features  of  the  mining  industry  in  Cali- 
fornia, and  in  which  will  be  found  a  description  of  the  geology 
of  all  the  deposits  of  economic  importance  in  the  State,  together 
with  maps  and  such  data  as  it  was  possible  to  obtain.  The 
geological  field  work  for  this  bulletin  was  performed  by  Mr. 
William  Forstner,  Assistant  in  the  Field,  of  the  State  Mining 
Bureau.  No  description  of  any  mine  or  prospect,  nor  of  the 
geology  of  any  part  of  the  territory,  has  been  given  except  after 
personal  investigation  by  Mr.  Forstner. 

In  treating  of  the  geology  and  the  genesis  of  ore  deposition, 
subjects  of  which  differences  of  opinion  exist,  endeavors  have 
been  made  to  present  as  briefly  and  clearly  as  possible  the 
different  opinions,  and  some  suggestions  have  been  added 
which  have  resulted  from  Mr.  Forstner's  personal  observation. 

In  the  chapter  on  the  metallurgy  of  quicksilver,  it  has  been 
the  aim  more  to  give  the  general  principles  upon  which  the 
different  methods  of  treatment  are  based  than  to  make  a  mere 
detailed  description  of  the  different  installations. 

The  courtesy  generally  shown  by  the  owners  and  superin- 


91575 


4  LETTER    OF   TRANSMITTAL. 

tendents  of  the  difierent  mines  deser\'es  special  mention.  With 
only  one  exception,  at  every  mine  all  information  which  would 
be  of  value  from  a  technical  and  often  from  a  commercial 
standpoint  was  given  with  the  greatest  courtes}-.  This  is  the 
more  appreciated,  as  quicksilver  is  a  product  for  which  the 
demand  is  to  a  certain  extent  limited,  and  it  is  only  natural 
that  operators  do  not  feel  inclined  to  disclose  all  the  facts  per- 
taining to  their  business. 

I  wish  to  extend  m}-  thanks  to  Mr.  J.  W.  C.  Maxwell,  who 
assisted  in  the  revision  of  the  technical  and  descriptive  portions 
of  the  bulletin;  to  Mr.  Charles  G.  Yale,  for  assistance  in  the 
editorial  part  of  the  work;  and  to  Mr.  E.  B.  Preston,  for  the 
classification  of  specimens  of  ores  and  formations  submitted. 

To  the   many   owners   and   superintendents  of   quicksilver 

mines  and  prospects  who  lent  their  assistance,  I  wish  also  to 

extend  my  thanks,  for  without  their  valuable  aid  it  would  have 

been  impossible  to  present  the  full  results  of  the  work  as  herein 

set  forth. 

Ver>-  respect  full}', 

LEWIS  E.  AUBURY, 

State  Mineralogist. 
San  Francisco,  June  30,  1903. 


CONTENTS. 


Page. 
CONDITION  OF  THE  INDUSTRY  .-..(» 

GEOLOGY  OF  THE  QUICKSILVER  BELT  IN  CALIFORNIA  12 

ORE  DEPOSITS            -------  23 

GENESIS  OF  QUICKSILVER  ORE  DEPOSITS       -            -  26 

COST  OF  MINING  AND  REDUCTION      -            -            -            -  34 

DISTRICTS  NORTH  OF  SAN  FRANCISCO: 

Mayacmas  District     ------  35 

Clear  Lake  District       -----  39 

Sulphur  Creek  District      -           -           -           -           -  40 

Knoxville  District         .           -           -           -           .  42 
QUICKSILVER  MINES  IN  THE  COUNTIES  OF  CALIFORNIA: 

Colusa  County        ------  43 

Lake  County     -------  46 

Napa  County           -           -           -           -           -           -  72 

Solano  County             -           -           -           -           -           -  93 

Sonoma  County       ------  97 

Yolo  County      -           -           -           -           -           -           -  117 

Fresno  County       ------  no 

Kings  County    -           -           -           -           -           -           -  122 

Monterey  County             -----  123 

San  Benito  County      ------  125 

San  Luis  Obispo  County  -----  144 

Santa  Clara  County  ------  Kjg 

Stanislaus  County           -----  igg 

El  Dorado  County       ------  190 

Trinity  County      -           -           -           -           -           -  190 

Other  Counties          ------  195 

METALLURGY       -------  197 

ELEVATIONS   -            -            -            -            -    '        .            -            -  254 


LIST  OF  ILLUSTRATIONS. 


SKETCHES. 


Figure.  Pagk 

1.  Section  of  northwest  slope  of  Pine 

Mountain,  Sonoma  County 38 

2.  Sulphur    Creek     District,    section 

over  Abbott  ridge 40 

3.  Abbott  mine,  Lake  County,  section 

over  the  serpentine 46 

4.  Abbott   mine,  Lake   County,  plan 

near    intersection     of    Reardon 
tunnel  and  first  level 47 

5.  Plan     and     elevation     of    Abbott 

mine    . _ faces    48 

6.  Big  Injun  group,  Lake  County 50 

7,  8.  Sections  of  Chicago  mine 52 

9.  Cross-section    of    Great    Western 

mine    54 

10.  Section  over  Great  Western  mine  .     55 

11.  Cross-section  of  Helen  mine.  Lake 

County    -- -.- -- 56 

12.  Plan  of  Lucitta  mine 59 

13.  Section  of  Bullion  mine  (Standard 

Quicksilver  Co.) _.     61 

14.  Sulphur  Bank  mine faces    62 

15.  Sulphur  Bank  mine,  elevation  of 

Upper  Wagon  Spring  Cut  at  X, .     63 

16.  Sulphur  Bank  mine,   section  and 

plan  of  Herman  shaft 67 

17.  Sulphur  Bank  mine,  ore  formation 

in  Herman  shaft tj8 

18.  Sulphur    Bank    mine,    section    of 

Diamond  shaft 69 

19.  Front  vievr  of  the  Wall  Street  mine, 

from  opposite  hill.side 71 

20.  ^Etna  Consolidated  mines 72 

21.  .Etna  Consolidated   mines,   eleva- 

tion at  mouth  of  Tunnel  No.  2..     74 

22.  .Etna   Consolidated   mines,  basalt 

dike,  Silver  Bow  claim 74 

23.  iEtna  Consolidated  mines,  section 

of  Washington  shaft... 75 

24.  Boston  mine,  section  over  the  min- 

eralizedzone 78 

25.  Corona  mine .faces    78 

26.  Corona     mine,     section     showing 

formation.  Dip  S.  W.  30' 79 

27.  Areal  geology,  Manhattan  mine, 

faces    80 

28.  Manhattan  mine,  section  over  the 

works  at  (f,) 87 

29.  Napa  Consolidated  mines,  general 

trend  of  veins 89 


Figure.  Page. 

30.  Napa  Consolidated  mines,  crossing 

of  two  veins  . .   .     91 

31.  St.   John    mine,  section  east   and 

west  over  main  tunnel  shaft 93 

32.  St.  John  mine,  plan  showing  main 

tunnel  west  of  shaft ...     96 

33.  St.  John   mine,  plan  of  works  in 

main  tunnel  shaft 96 

34.  Cloverdale     mine,     section      over 

works.  Mount  Vernon  claim 99 

35.  Cloverdale  mine 100 

36.  Cloverdale  mine,  plan  and  section 

of  Murphy  tunnel .  101 

37.  Plan  of  Crown  Point  and   Pacific 

mines _ .  103 

38.  Section  of  Culver-Baer  mine...  ...  104 

39.  Eureka  mine 107 

40.  Great  Eastern  mine,  general  plan, 

faces  108 

41.  Section    over    the    Great    Eastern 

mine 108 

42.  Great  Eastern  mine,  plan  showing 

the  form  of  the  ore  bodies 111 

43.  Socrates  mine 116 

44.  Plan    of    Mexican     mine,    Fresno 

County 120 

45.  Workings,  Bradford  mine 132 

Cerro  Bonito  mine  . 134 

46.  Elevations  open  cut  (6),  Cerro  Bo- 

nito mine 136 

47.  New  Idria  mine     140 

48.  Plan  of  New  Idria  mine 141 

49    Section  west  end  of  fifth  level.  New 

Idria  mine 142 

50.  Open  cut,  San  Carlos  mine 144 

51.  Section  at  Gray  buck  shaft,  Stayton 

mine 148 

52.  Plan  of  .\lice  and  Modoc  mine 1-55 

53.  Libertad  tunnel  No.  2  160 

54.  Lower    Ocean   View  tunnel.   Pine 

Mountain  Mine 164 

55.  Section   near   R    R.  B.  shafl,  New 

Almaden  property. 170 

56.  Section  on  road  above  Randol  shaft, 

New  Almaden  mine ...   170 

57.  Ore  bodies  in  the   New  jVlmaden 

mine .faces  174 

58.  Section  of  Mine  Hill,  New  Alma- 

den  178 


LIST   OF    ILLUSTRATIONS. 


Figure  Page. 

59.  Section     over    Santa     Rita     West, 

Giant   Powder  stopes,    New   Al- 
maden    178 

60.  Plan  of  the  clay  walls,  New  Alma- 

den    mine   (from    Atlas,    Mono- 
graph XIII,  V.  S.  G.  S.) ./aces  184 

61.  Section   in   Enriquita   mine,   New 

Almaden -._ 185 

62.  Sketch    of    works    in     the    Santa 

Teresa  mine _ 186 

Trinity  County  quicksilver  districts  191 
6.1a .  U  nderg^ound  workin  gs  of  In  tegral 

„-        mine 194 

63y  Plan  and  elevations  of  concentrat- 

@ing  system,  Manzanita  mine 199 
Pipe    retort    furnace,    by    G.     V. 
Northey 201 

65.  Condensing  plant,  soot  retort,  Bos- 

ton mine 202 

66.  Johnson  &  McKay  furnace 203 

67.  Continuous  retort,  quicksilver  fur- 

nace   204 

68.  Exeli  furnace  -  _ 209 

69.  Knox  &  Osborne   coarse-ore    fur- 

nace..     ._  211 

70.  Coarse-ore    furnace,    John    Neat's 

patent 212 

71.  New  Idria  coarse-ore  furnace 213 

"i*.  Longitudinal      section,     modified 

Livermore  quicksilver  furnace..  215 
73.  Knox  &  Osborne  fine-ore  furnace.  216 


GURE.                                                 Page. 
Plan  of  Hiittner  &  Scott  8-tile  fur- 
nace  220 

Tilings  of  Furnace  No.  3,  New  Al- 
maden   221 

Tiling  of  Cermak-Spirek  furnace..  221 
Ore-drier,  utilizing  exhaust  steam .  225 
Ore-drier,  special  furnace  at  Abbott 

mine 227 

New  Idria  fine-ore  furnace — meth- 
od of  conveying  fumes  from  top.  228 
Top  of  the  modified  Scott  furnace.  229 
Top  of  Hiittner  &  Scott  furnace  ...  230 

Discharge  Scott  furnace.   2.32 

New  Idria  fine-ore  furnace,  details 

of  drawing  door 234 

General   plan  of  reduction  works 
(from  Mineral  Industry,  Vol.  7), 

between  234-235 
Sketch  showing  method  of  hand- 
ling ore  at   Abbott  mine.  Lake 

County 236 

.  Plan  of  works 237 

Details  of  condensers 237 

,  Installation  to  save  flour  mercury. 

New  Almaden 240 

Scott's  brick  condenser  plant 248 

Knox  ironclad  condenser _.  249 

Watertank  condenser..    250 

The  Baker  flue 251 

Wooden    condenser    box,    Corona 

mine.. 252 

Soot-cleaning  machine 253 


PHOTOGRAPHS. 


No.  Page. 

1.  Chicago  plant 51 

2.  Great  Western  quicksilver  mine  ..  53 
3    Western  cut.  Sulphur  Banks 62 

4.  .^itna  quicksilver  mine 73 

5.  Boston  quicksilver  mine 77 

6.  Manhattan  quicksilver  mine 81 

7.  Oathill  quicksilver  mine .  90 

8.  St.  John  mine  and  furnace 94 

9.  St.  John  quicksilver 'mine 94 

10.  Great  Eastern  quicksilver  mine.   .  109 

11.  Thin  section  of  sandstone  and  ser- 

pentine from  New  Idria  district.  127 

12.  View  of  New  Idria 1:59 

1:'..  Los  Picachos  mine  (Ramirez  Con- 
solidated)  146 

14.  La  Libertad  mine 159 

15.  General    view   of    New    Almaden 

mine 175 

ir>.  Dump    of     New    Almaden     mine 

works 179 

17.  Durapof  Grey  shaft  and  Mine  Hill, 

New  Almaden 180 

18.  Victoria  shafl,  New  .\lmaden 181 


P.4.GE. 
Santa  Isabel  shaft.  New  .\lraaden  .  182 

Randol  shaft.  New  Almaden. 183 

Entrance     Castella     development 

tunnel.  Integral  mine 193 

Pipe-retort     furnace.     Manzanita ^ 

mine,  Colusa  County ^200 

Corona  furnace 207" 

Tufa  furnace  in  course  of  construc- 
tion. Corona  quicksilver  mine. . .  207 
New  Idria  quicksilver  mine,  show- 
ing new  SO-ton  coarse-ore  furnace  214 

Cloverdale  reduction  plant 217 

Great  Western  Quicksilver  Mining 

Company's  reduction  plant 217 

Manhattan  furnace 218 

Altoona  quicksilver  mine 219 

Furnace     plant,     Integral     mine, 

Trinity  County 222 

Karl  furnace,  San  Luis  Obispo 224 

Great  Eastern  mine,  drying  ore  in 

sun "226 

Reduction  works  at  New  Almaden, 
Hacienda  231 


8 


LIST    OF    ILLUSTRATIONS. 


No.  Page. 

34.  General  view  of  reduction  works 

at  New  Almaden,  Hacienda 233 

35.  Furnace  Nos.  1  and  2,  New  Alma- 

den, Hacienda 233 

36.  Reduction  plant  in  cour.se  of  con- 

struction, Silver  Creek  Quick- 
silver Mining  Company,  Santa 
Clara  County 235 

37.  Reduction     plant,     Silver     Creek 

Quicksilver  Mining  Company, 
Santa  Clara  County  238 

38.  Great  Eastern  furnaces 239 

39.  New  Idria  mine,  showing  Scott  fur- 

nace  _ _. 241 

40.  Boston  quicksilver  mine,  quicksil- 

ver furnace 242 

41.  Flues  connecting  furnace  with  con- 

denser plant.  New  Almaden, 
Hacienda - 242 


No.  Page. 

42    Oceanic      quicksilver      reduction 

plant,  San  l,uis  Obispo  County.  243 

43.  Interior  view  of  reduction  works. 

New  Almaden.  Hacienda 245 

44.  New  Idria,  showing  round  wooden 

flue  and  wooden  tanks  used  for 
condensers 245 

45.  Retorting  soot,  Great  Eastern 246 

Ferry    building,   San    Francisco,   one 

half  of  which  is  occupied  by  the 
State  Mining  Bureau 261 

Mineral  Museum,  California  State 
Mining  Bureau __.  263 

Library  and  free  reading-room,  Cali- 
fornia State  Mining  Bureau 265 

Laboratory,  California  State  Mining 
Bureau 267 

Draughting  department,  California 
State  Mining  Bureau 269 


MAPS— (Folders). 

P.\GE. 
Geological  map  of  portions  of  Napa,  Sonoma,  and  Lake  County  quicksilver  districts, 

California     _ ._ _ 35 

Geological  map  of  Napa,  Sonoma,  Lake,  and  Yolo  County  quicksilver  deposits 39 

Map  of  Sulphur  Creek  District _ _ .   40 

Map  of  Little  Panoche  Mining  District _ 118 

Geol  ogical  map  of  quicksilver  districts  in  southern  portion  of  San  Benito  County . .  _  126 

Geologfical  map  of  Stay  ton  Mining  District.   ._.    129 

Geological  map  of  quicksilver  districts  northwestern  portion  of  San  Luis  Obispo 

County   ...     149 

Map  of  the  New  Almaden  Mining  District 168 


THE  QUICKSILVER  RESOURCES 
OF  CALIFORNIA. 


By  WM.  FORSTNER,  E.M. 

Assistant  in  the  Field. 


CONDITION  OF  THE  INDUSTRY. 


Quicksilver  has  been  produced  in  California  since  1850.  The 
table  published  in  the  report  of  the  Eleventh  Census  (1890), 
page  188,  compiled  bj'  Mr.  J.  B.  Randol,  giving  the  annual  pro- 
duction of  the  various  mines  from  1850  to  1889,  indicates  that 
in  the  decade  1850  to  i860  the  Xew  Almaden  mine  was  about 
the  onl}-  producer.  In  the  latter  part  of  the  6o's,  the  New 
Idria,  Redington,  and  i^tna  mines  began  to  produce.  The 
greatest  number  of  mines  were  in  operation  between  the  years 
1874  and  1880.  This  activity  was  due  to  the  high  price  of 
quicksilver  obtained  in  1874,  when  the  prices  per  flask  in  San 
Francisco  were:  highest,  $126.22;  lowest,  $84. 15.  In  1875  the 
price  dropped  to  $49.75,  and  until  1883  the  average  price  was 
about  $30.  The  lowest  price  was  in  this  period  for  awhile, 
$25.  For  years  the  price  remained  rather  low,  but  in  the  last 
few  3-ears  it  has  maintained  a  figure  which  gives  the  operators 
a  fair  remuneration.  These  low  prices  in  1879  and  1880  caused 
the  closing  of  a  number  of  quicksilver  mines,  and  for  some 
years  quicksilver  mining  was  carried  on  only  at  a  few  of  the 
large  mines.  In  later  years  the  price  of  quicksilver  has  risen, 
although  by  no  means  to  that  of  the  prosperous  times,  and 
graduall}-  the  old  mines,  closed  for  years,  are  being  reopened. 
In  the  meanwhile  the  older  mines,  which  have  been  steady 
producers  for  many  years,  appear  to  have  worked  out  their 
bodies  of  high-grade  ores,  and  are  all  now  working  what  in 

(9) 


10 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


years  past  would  have  been  classed  as  poor  ores.  In  the  well- 
managed  properties,  however,  where  they  have  availed  them- 
selves of  the  more  economical  methods  of  mining  and  especially 
of  reducing  the  ores,  a  fair  interest  on  the  investment  is  earned 
from  these  low-grade  ores.  The  yearly  production  of  quick- 
silver in  California  has  been  as  follows: 

TABLE    GIVING    YEARLY    PRODUCTION    OF    CALIFORNIA    MINES    AND 
AVERAGE   PRICE   PER  FLASK   IN  SAN  FRANCISCO. 


Flasks 

Year.  Produced. 

1850  [a) 7,723 

1851 27,779 

1852 20,000 

1853 22.284 

1854 3O1OO4 

1855 33,000 

1856 30,000 

1857  W 28,204 

1858 31,000 

1859 13,000 

i860 10,000 

1861 35,000 

1862 42,000 

1863 40,531 

1864 47,489 

1865 53.000 

1866 46,550 

1867 47,000 

1868 47,728 

1869 33,8x1 

1870 30,077 

1S71  31,686 

1872  31,621 

1873 27,642 

1874 27,756 

1875 50,250 

1876 75,074 

1877 79,396 

1878 63,880 


Average 

Price  per 

Flask. 

V 

$99  45 

I 

66  93 

I 

58  33 

1 

55  45 

I 

55  45 

I 

53  55 

I 

51  65 

I 

48  73 

I 

47  83 

I 

63  13 

I 

53  55 

I 

42  05 

I 

36  35 

I 

42  08 

1 

45  90 

I 

45  90 

I 

53  13 

I 

45  90 

I 

45  90 

I 

45  90 

Ic 

57  38 

II 

63  10 

K 

65  93 

IC 

80  33 

I( 

105  18 

I( 

84  15 

K 

44  00 

K 

37  30 

It 

32  90 

Flasks 
Produced. 

1879 73,684 

1880 59,926 

il 60,851 

£882 52,732 

1883 46,725 

t884 31,913 

[885  . 32,073 

[886  29.981 

1887  (<r) 33,760 

1888 33,250 

1889  26  464 

22  926 

[891 22,904 

1892 .  27,993 

i893(d?) 30,164 

30,416 

C895 36,104 

1896 30,765 

1897 26,648 

[898 3^,092 

1899 29,454 

[900 26,317 

[901  26,720 

1902 29,552 

1903 32,094 

[904 28,876 

[905.........  24,655 

[906 19,516 


Average 

Price  per 

Flask. 

$29 

85 

31 

00 

29 

83 

28 

23 

28 

75 

30  50 

30 

75 

35 

50 

42 

37>^ 

42 

50 

45 

00 

52 

50 

45 

25 

40  71 

36 

75 

30 

70 

37  04 

34 

96 

37 

28 

38 

23 

47 

70 

44  94 

48  46 

43 

20 

42 

25 

37 

62 

35 

94 

36 

50 

(<7)  Report  nth  Census.  1850  to  1865,  great  bulk  of  quicksilver  produced  by  the 
New  .\ltQaden  mine. 

16)  The  New  Idria  mine  begins  to  produce  1857. 

(c)  From  1887  to  1893,  Dr.  Day's  Report,  U.  S   Geol.  Survey. 

(rf)  1893  to  date.     Annual  Statistical  Bulletins,  California  State  Mining  Bureau. 

Quicksilver  furnaces  are  great  consumers  of  wood,  and  even 
those  mines  which  are  located  in  well-timbered  regions  find 
the  cost  of  their  fuel  steadil}'  increasing.  Only  in  exceptional 
cases  can  mines  get  their  cordwood  delivered  for  $3.50  per 
cord;  generally  the  price  is  higher,  in  some  cases  double  that 
figure.  Hence  most  of  the  quicksilver  mine  managers  are 
eagerly    looking    for    a    substitute    for    cordwood    as    fuel   in 


CONDITION    OF   THE    INDUSTRY.  11 

their  furnaces.  Up  to  the  present  time,  however,  this  has  not 
been  found. 

As  mentioned  above,  many  of  the  quicksilver  mines  have 
been  idle  for  some  years,  and  of  these  it  is  very  difficult  to 
obtain  either  reliable  historical  data,  or  details  of  the  old  work- 
ings or  of  the  output  of  mercury.  Even  in  the  mines  which 
have  been  in  continuous  operation,  large  portions  have  been 
worked  out  and  abandoned,  and  it  is  nearly  impossible  to  get 
the  desired  information  regarding  these  portions  of  the  mines. 
In  regard  to  several  of  the  principal  mines  of  the  State,  belong- 
ing to  the  Napa  Consolidated  and  affiliated  companies,  these 
data  were  to  a  great  extent  destroyed  in  1898,  in  which  year 
the  main  office  in  Oathill  was  burned  and  most  of  the  mine 
maps,  etc.,  were  destroyed. 

Whatever  information  of  this  character  it  was  possible  to 
collect,  is  inserted  in  the  descriptions  of  the  respective  mines. 
It  may  here  be  stated  that  in  accordance  with  the  general 
scheme  of  this  Bulletin,  its  contents  are  confined  strictly  to 
the  occurrence  of  quicksilver  in  the  State  of  California,  for 
which  reason  all  reference  to  mines  and  works  in  other  locali- 
ties is  omitted. 


GEOLOGY  OF  THE  QUICKSILVER  BELT 
IN  CALIFORNL\. 


The  quicksilver  deposits  in  California  are,  with  a  few  scat- 
tered exceptions,  located  in  the  Coast  Ranges.  There  is  a  ver>' 
marked  difierence  of  opinion  among  the  geologists  who  have 
made  a  special  study  of  this  territory,  regarding  two  points: 
First,  as  to  the  age  of  the  metamorphic  series  which  form  such  a 
prominent  part  of  the  rocks  in  this  territory;  and  secondly,  as 
to  the  origin  of  the  serpentine.  Thej^  all  agree  that  violent 
geological  disturbances  took  place  in  this  region  at  some  period 
within  the  Mesozoic  age.  These  disturbances  were  sudden  and 
sharp,  resulting  in  the  crushing  and  fracturing  of  the  strata 
rather  than  their  uplifting  and  folding  [Whitnej',  Auriferous 
Gravels,  page  15],  and  gave  this  series  a  characteristic  struc- 
ture, which  serves  to  its  identification.  The  epoch  of  this 
revolution  is  placed  by  Becker  at  the  end  of  the  Xeocomian  or 
Lower  Cretaceous,  while  Fairbanks  and  others  place  it  at  the 
close  of  the  Jurassic  epoch,  hence  as  pre-Cretaceous. 

The  rock  series  metamorphosed  b}-  the  revolution  is  called 
by  Becker  the  Xeocomian,  and  also  occasionally  the  Metamorphic 
series;  by  Fairbanks,  the  Pre-Cretaceous  or  the  Metamorphic 
series;  by  Lawson,  the  Franciscan  series.  These  rocks  rest 
upon  a  basement  complex  consisting  of  crystalline  limestones 
and  schists  and  granites.  The  granite  does  not  appear  at  the 
surface  north  of  the  bay  of  San  Francisco,  except  on  the  coast 
twenty  miles  north  of  San  Francisco  at  Point  Tomales;  but 
south  of  San  Francisco  there  are  two  ages  of  granitic  uplifts. 
The  granite  is  intrusive  in  the  older  strata.  The  crystalline 
rocks  of  the  basement  complex  are  only  found  at  a  few  points; 
the  granitic  uplifts  brought  them  within  a  zone  of  such 
efiective  erosion  that  the  granite  was  almost  entirely  denuded 
before  the  next  period  of  subsidence  and  deposition  of  the 
Franciscan  series  set  in.  The  age  of  the  crystalline  rocks  of 
the  basement  complex  is  either  Carboniferous  or  older.  [See 
Bulletin  Geological  Society  of   America,  vol.  VI,  pages  79-81.] 

(12) 


GEOLOGY    OF   THE    QUICKSILVER    BELT.  13 

Intimately  mingled  with  the  rocks  of  the  Franciscan  series 
are  large  masses  of  serpentine.  Becker  holds  that  these  are 
prominently  altered  sedimentaries  [see  Mineral  Resources,  1892, 
U.  S.  G.  S.,  page  144];  while  Fairbanks  holds  these  serpen- 
tines to  be  exclusivel}^  derived  from  eruptives.  A.  C.  L,awson 
is  of  the  same  opinion,  so  far  as  the  serpentines  in  the  penin- 
sula of  San  Francisco  are  concerned.  Apparenth'  the  latter 
views  as  to  the  origin  of  the  serpentine  in  the  Coast  Ranges 
are  entertained  by  all  the  geologists  on  the  Pacific  Coast.  The 
serpentine  bodies  occur  in  different  forms  and  the  rocks  them- 
selves vary  very  sensibly  in  structure  in  different  regions  and 
in  the  various  bodies  of  serpentine.  In  places  the  serpentine 
occurs  in  bodies  indicating  an  original  dike  formation  and 
showing  intrusive  phenomena;  while  in  other  places  large 
areas  of  serpentine  occur  which  can  hardly  be  conceived  to  be 
derived  from  eruptive  masses,  and  wherein  are  found  small 
areas  of  sandstone  and  occasionally  shales,  indurated  but 
slightly  altered,  in  places  even  unaltered.  In  other  places  the 
serpentine  overlies  or  underlies  the  sandstone  and  shales  with- 
out any  intrusive  phenomena.  During  the  investigation  in 
the  preparation  of  this  Bulletin,  in  the  neighborhood  of  New 
Idria  [see  general  description  of  the  New  Idria  district,  page 
125]  and  near  Cambria,  San  Luis  Obispo  County,  sandstone  and 
serpentine  were  found  intimately  associated.  Samples  of  these 
occurrences  are  in  the  museum  of  the  State  Mining  Bureau, 
and  a  slide  of  the  first  mentioned  has  been  prepared  and 
photographed. 

Both  views  of  the  origin  of  the  serpentine  can  be  sustained 
by  microscopical  examination.  [See,  for  instance,  Becker, 
Mon.  XIII,  U.  S.  G.  S.,  page  275,  and  following;  A.  C.  Law- 
son,  15th  Ann.  Report,  U.  S.  G.  S.,  pages  417,  433,  and  447; 
etc.]  It  may  be  argued  that  both  views  are  correct  and  that 
probably  the  serpentine  is  an  alteration  product  of  both  sedi- 
mentaries and  eruptives  in  this  region,  as  is  the  case  elsewhere. 
This  view  is  that  of  the  majority  of  geologists.  In  1888  this 
question  was  submitted  to  the  American  Committee  of  the 
International  Congress  of  Geologists  [.see  American  Geologist, 
vol.  II,  page  180],  in  the  following  form: 

Question  N — Is  serpentine  (i)  sometimes,  (2)  always  an 
alteration  product,  (3)  of  eruptives,  (4)  of  sedimentaries,  (5)  of 
either? 


14  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

Thirteen  answers  were  received,  which  can  be  summarized 
as  follows:  Twelve  declared  serpentine  to  be  an  alteration 
product,  and  one  characterized  it  as  an  original  aqueous  rock. 
Three  of  the  first  twelve  took  the  view  that  it  is  exclusively  an 
alteration  product  of  igneous  rocks;  one  exclusively  of  sedi- 
mentar\'  rocks;  two,  generalh'  of  igneous  rocks,  but  could  also 
be  such  of  sedimentarN'  rocks;  and  five  that  it  is  an  alteration 
product  of  both  eruptive  and  sedimentary  rocks,  while  one 
leaves  this  part  of  the  question  unanswered. 

Professor  van  Hise  remarks,  in  his  Principles  of  North 
American  Pre-Cambrian  Geology  [i6th  Ann.  Report,  U.  S. 
G.  S.,  Part  I,  page  68g]  :  "Actinolite,  serpentine,  and  magnetite 
"have  been  observed  to  replace  quartz.  In  the  case  of  the  two 
"former  minerals  their  relation  to  the  quartz  suggests  that  the 
"other  constituents,  with  the  exception  of  silica,  were  at  hand 
"or  were  furnished  b}"  the  percolating  water  out  of  which  the 
"serpentine  and  actinolite  formed;  and  that  the  quartz  itself 
"ma}'  have  furnished  the  necessary  silica  to  produce  these 
"minerals."  [On  page  691:]  "Among  basic  sedimentan,- rock 
"serpentine  very  often  develops." 

E.  S.  Dana  [Mineralogy,  1898,  page  477]  states:  "Microscopic 
"examination  has  established  the  fact  that  serpentine  is  largely 
"produced  by  the  alteration  of  chrysolite;  in  other  cases  it  has 
"resulted  from  the  alteration  of  pyroxene  or  amphibolite." 
[See  also  Williams,  Lithology,  page  254.] 

A.  C.  Lawson,  in  describing  the  deformations  of  the  earth- 
crust  which  have  influenced  the  geology  of  the  San  Francisco 
peninsula  [15th  Ann.  Report,  U.  S.  G.  S.,  page  466],  mentions 
"an  invasion  of  the  upper  portion  of  the  Franciscan  series  by 
"peridotite  magma,  which  solidified  in  the  form  of  dikes  or 
"laccolitic  lenses." 

The  granites  of  that  part  of  the  Coast  Range  which  contains 
the  quicksilver  belt  appear  only  at  the  surface  south  of  San 
Francisco.  Lawson  has  carefully  studied  granite  in  two 
places:  the  Montara  granite  in  the  San  Francisco  peninsula 
[above  cited,  page  411],  which  he  describes  as  a  coarse  gray 
hornblende,  biotite  granite,  which  originally  was  a  hornblende 
granite;  and  at  Carmel  Bay  [Bulletin  Geological  Department, 
University  of  California,  vol.  I],  which  he  describes  as  a  coarse 
porphyritic  granite.  Similar  granite  rocks  are  found  in  the 
Santa  Lucia  Peak,  and  in  the  San  Jose  range. 


GEOLOGY   OF   THE    QUICKSILVER    BELT.  15 

Fairbanks  has  studied  extensively  the  granites  in  the  Coast 
Range  south  of  San  Francisco,  and  considers  them  as  true 
mica  feldspar  quartz  granites,  difiering  from  the  granites  in  the 
Sierra  Nevada,  which  are  usually  hornblendic.  [Bulletin  Geo- 
logical Society  of  America,  vol.  VI,  page  79.] 

H.  W.  Turner  [Am.  Geol.,  vol.  XI,  page  324]  supposes  these 
granites  to  be  of  Carboniferous  age.  Fairbanks  thinks  this 
may  be  true  or  they  may  be  older. 

Accepting  the  suggestion  of  Becker  that  the  entire  Coast 
Range  is  underlaid  by  granite  [Mon.  XIII,  page  140],  a  source 
of  ferro-magnesian  silicates  other  than  the  suggested  post- 
Franciscan  peridotite  intrusions  is  present  in  this  region.  Law- 
son  [above  cited,  page  434]  calls  attention  to  the  fact  that  the 
entire  period  of  accumulation  of  the  Franciscan  series  was 
a  period  of  volcanic  activity,  and  that  the  lower  portions  of 
this  series  were  traversed  by  igneous  rocks,  which  arriving  at 
the  surface,  became  constituents  of  the  upper  portion  of  the 
series. 

It  appears  most  probable  that  all  of  these  materials  have 
contributed  to  the  formation  of  the  bodies  of  serpentine  found 
in  this  region.  As  van  Hise  remarks  [above  cited,  page  691], 
"  Material  for  the  serpentines  maybe  furnished  in  part  or  in 
"whole  by  minerals  present,  or  the  material  of  the  serpentine 
''may  come  from  an  extraneous  source.  Also,  widespread  for- 
"mations  may  be  extensively  serpentinized,  so  as  to  give  for 
"considerable  areas  almost  solid  masses  of  serpentine." 

The  pressures  which  caused  these  deformations  produced 
great  heat  from  dynamic  action,  which  was  increased  by  that 
obtained  from  the  intruding  magmas;  consequently  both 
pressure  and  temperature  were  raised  during  the  deformations, 
causing  an  increased  chemical  activity  of  the  circulating 
waters,  and  it  appears  only  reasonable  to  assume  that  all 
available  sources  for  the  formation  of  serpentine  masses  were 
called  upon. 

The  later  intrusions,  forming  the  dike  and  laccolitic  lenses, 
can  be  generally  defined  by  the  phenomena  of  contact  meta- 
morphism  accompanying  them;  while  the  large,  widely-dis- 
tributed ma.sses  of  serpentine  were  probably  formed  by 
magnesian  solutions  acting  upon  the  rock  material.  [Mon. 
XIII,  pages  1 21-127,  ^^^d  273-278.]  The  ferro-magnesian 
silicates  are  probably  derived  from  the  basal  granite,  and  per- 


16 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


haps  from  intrusives,  which  would  explain  the  entire  lack  of 
contact  metamorphism  phenomena  at  the  contact  of  many  ser- 
pentine bodies  with  the  other  rocks.  This  lack  of  contact 
metamorphism  and  intricate  mixture  of  serpentine  with  the 
sandstones  and  shales  of  the  Franciscan  series,  and  even 
probabl3'  with  the  schists  of  the  basal  complex,  can  be  exten- 
sively studied  in  the  New  Idria  district. 

As  already  stated  above,  there  is  a  great  diversit}'  of  opinion 
as  to  the  historical  geology  of  the  Coast  Ranges.  The  accom- 
panying table  of  comparison  will  set  this  forth.  [See  American 
Geologist,  vol.  XL] 


AGE.          Period. 

Gabb — 

CALI- 
FORNIA. 

WHITE  AND          '           °STAVTOn''° 

C^Li'f'oRnTa               NORTHCrLIPOR-          I'^-^^-' 
CALIFORNIA.            ^.j^  ^^^  OREGON. 

Cenozoic. 

Miocene. 
Eocene. 

Chico  Tejon. 

Probable  place  of 
the  Wallalla. 

Tejon. 

Monterey 

Series. 

Light  color'd 

Sandstone? 

Upper 
Cretaceous. 

Tejon. 

Martinez. 

Chico. 

V, 

.a 

'C 

V 

m 
o 

■I 
(J 

5 
7. 

Hiatus 
and 
nconformity.     ^            r. 

:             '*- 

'Chico.                 j           « 

o 

N 

O 
Ol 

Lower 
Cretaceous. 

Shasta. 

Hiatus  of  White. 

Unconformity  of 

Becker. 

.  fHorsetown. 

i  i  Knoxville, 
j:     including 
'"^  L  Mariposa. 

Horsetown. 

t  Knoxville. 

a 
a 
u 

•s 

a 

1 

Jurassic. 

Mariposa. 

Mariposa. 

This  difference  of  classification  is  closely  related  to  the  above- 
mentioned  difference  of  opinion  as  to  the  period  wherein  took 
place  the  disturbances  which  caused  the  metamorphism  of  the 
rocks  deposited  after  the  first-recorded  intrusions.  J.  S.  Diller 
says  [Bulletin  Geological  Society  of  America,  vol.  IV,  page 
2o6]  :  "  The  Cretaceous  of  north  California,  embracing  the 
"  Chico,  Horsetown,  and  Knoxville  beds,  are  essentiall}^  con- 
"  formable,  hence  the  upheaval  must  have  been  pre-Neocomian." 
Becker  places  the  upheaval  after  the  Horsetown  series,  refer- 
ring to  it  as  post-Xeocomian.  Fairbanks  indorses  Diller's 
opinion,  and  names  the  Metamorphic  series  the  Pre- Cretaceous 
series. 


GEOLOGY   OF   THE    QUICKSILVER    BELT.  l7 

Whatever  may  be  its  age,  this  Franciscan  series  presents  some 
distinguishing  characteristics  which  facilitate  its  identification 
from  the  underlying  crystalline  limestones  and  schists  of  the 
basement  complex,  and  from  the  overlying  younger  rocks. 
This  series  consists  mainly  of  sandstones,  associated  with  some 
shales,  cherts,  and  occasionally  limestone.  The  sandstones  are 
rather  massive;  the  bedding  planes  have  often  intercalated 
beds  of  shale.  They  are  very  generally  altered  through  a 
process  of  recrystallization  and  cementation  by  silicification. 
All  grades  of  alteration  can  be  observed,  from  nearly  unaltered 
arkose  sandstone  to  compact  jasper,  or  jaspilite  (a  term  sug- 
gested by  Wadsworth).  [See  i6th  Ann.  Rep.  U.  S.  G.  S., 
Pt.  I,  page  702.]  Interbedded  with  the  sandstones  are  lime- 
stones, cherts,  and  volcanic  rocks. 

The  chert  beds  form  a  very  characteristic  member  of  this 
series,  but  are  much  more  prominent  in  the  districts  north  of 
San  Francisco  than  in  those  south.  They  have  been  exten- 
sively discussed  by  Becker,  Fairbanks,  and  Lawson.  The 
first  named  refers  to  them  as  schistose  rocks  which  have  been 
subjected  to  a  process  of  silicification,  and  classes  them  as 
phthanites.  Blake  supposed  that  they  had  resulted  from  the 
metamorphism  of  shales  and  sandstones  by  igneous  action. 
J.  J.  Newberry  [General  Geology  of  California,  page  66]  says: 
"  Whether  the  material  of  which  they  are  composed  is  thrown 
"  up  from  below,  or,  as  is  more  probable,  it  is  a  metamorphosed 
"  form  of  the  associated  rocks,  it  is  evident  that  the  material 
"  has  been  subject  to  great  heat."  Fairbanks  [Bulletin  Geo- 
logical Society  of  America,  vol.  VI,  page  71]  classifies  this 
formation  as  jasper.  Lawson  [above  cited,  page  420]  as 
Radiolarian  cherts,  which  designation  appears  the  most  correct. 

The  following  is  a  concise  statement  of  Mr.  Lawson's  study 
of  this  formation : 

"These  beds  consist  of  alternate  thin  sheets  of  chert,  rang- 
"ing  generally  from  one  to  four  inches  in  thickness,  only 
"  exceptionally  having  a  much  greater  thickness,  with  part- 
"ings  of  shale  from  one  eighth  to  one  half  inch  thick.  Some- 
"  times  the  regularity  is  much  less  marked,  and  in  the  less 
''ferruginous  varieties  of  the  chert  beds  the  sheets  of  chert 
"assume  occasionally  a  lenticular  form.  The  difference  of 
"opinion  as  to  the  proper  classification   of  this  formation   is 

2— QR 


18  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

"due  to  the  fact  that  petrographically  these  cherts  are  not 
"uniform.  In  many  cases  they  are  true  jaspers;  in  others 
"the  silica  is  chiefly  amorphous,  and  the  rocks  have  a  flinty 
"character;  in  still  other  cases  the  proportion  of  iron  oxide 
"is  so  great  that  the  cherty  character  disappears  and  the 
"beds  become  locally  very  soft.  All  gradations  between 
"cherts  composed  almost  wholly  of  amorphous  silica,  to  those 
"which  are  a  holocrystalline  aggregate  of  quartz  granules, 
"are  found.  The  amorphous  silica  differs,  however,  from  opal, 
"in  that  it  has  a  much  higher  specific  gravity  and  contains 
"much  less  combined  water.  The  cherts  are,  then,  minutely 
"granular  aggregates  of  cr^^stalline  silica,  tending  more  toward 
"the  chalcedonic  than  to  the  quartz  variety,  with  varying  pro- 
"  portions  of  amorphous  silica,  mixed  with  ferric  oxide  and 
"ferric  hydrate,  sometimes  uniformly  distributed,  or  again  in 
"patches  or  streaks.  The  mass  is  intersected  bj'  numerous 
"small,  often  microscopical  veins,  the  smaller  filled  with  chal- 
"cedonic,  the  larger  with  quartzose  silica,  and  occurring  in  two 
"sets  of  fissures  crossing  at  high  angle.  Zoisiteis  often  found 
"in  the  vein  filling.  These  chert  beds  contain  round  or  oval 
"spaces,  occupied  by  chalcedony,  which  are  the  residual  casts 
"of  Radiolaria.  The  intervening  shale  consists  of  silica,  iron, 
"considerable  magnesia,  and  a  small  amount  of  alumina  with- 
"out  any  clastic  material.  The  association  of  chert  beds  with 
"the  sandstone  precludes  the  possibility  of  their  formation 
"under  deep-sea  conditions,  which  would  be  indicated  by  the 
"absence  of  fragmental  material." 

The  most  probable  hypothesis  of  their  formation  is,  as  sug- 
gested by  lyawson,  that  the  silica  was  derived  from  siliceous 
springs  and  precipitated  in  the  bed  of  the  ocean  in  local  accu- 
mulations, in  which  Radiolarian  remains  were  imbedded.  The 
alteration  of  the  beds  of  chert  with  partings  of  shale  may 
perhaps  be  ascribed  to  an  intermittent  action  of  the  springs. 
These  chert  beds  occur  throughout  the  Coast  Range  in  a  spo- 
radic manner,  and  are  especially  of  interest,  as  in  some  mines 
they  form  the  ore-bearing  zones.  Associated  with  these  rocks 
of  the  Franciscan  series  are  metamorphic  schists  which  appear 
to  represent  stages  of  alteration  of  rocks  of  very  diverse  origin, 
and  may  be  principally  the  result  of  contact  metamorphism, 
which,  as  H.  W.  Turner  remarks,  "is,  however,  yet  to  be  fully 
demonstrated."     As    already  stated  above,   the  rocks  of  this 


GEOLOGY   OF   THE    OUICKSIL\^R    BELT.  19 

series  are  further  associated  with  many  and  various  igneous 
intrusives,  entirely  separate  from  the  later  Tertiary  and  post- 
Tertiary  igneous  ejections. 

There  must  have  been  a  considerable  difference  in  the  geo- 
logical history  of  the  northern  and  southern  part  of  the  quick- 
silver belt.  South  of  San  Francisco  the  Franciscan  series  were 
elevated  and  eroded  to  such  an  extent  that  the  Tejon  is  found 
resting  directly  on  the  granite  and  a  second  elevation,  and 
post-Miocene  erosion  must  have  followed,  as  the  Pliocene  is 
also  found  resting  direct  on  the  granite.  North  of  the  bay  of 
San  Francisco,  the  erosion  of  the  Franciscan  series  has  been 
much  less,  so  that  between  the  bay  and  Clear  Lake  the  granite 
does  not  appear  at  the  surface  and  the  younger  formations  all 
rest  on  this  series. 

The  metamorphism  of  the  Franciscan  series  was  eminently 
a  process  of  recrystallization  of  the  clastic  sediments  into  holo- 
cr^'stalline  feldspathic  rocks,  carrj'ing  ferro-magnesian  silicates, 
and  in  the  formation  of  vast  quantities  of  serpentine.  [See 
Becker,  above  cited,  page  57.]  The  serpentinization  was  pos- 
terior to  the  former  process,  which  included  a  silicification  which 
altered  part  of  the  shales  to  jaspery  masses  and  formed  in  these 
and  in  other  rocks  innumerable  minute  veins  of  quartz.  \_Ibid., 
page  393-] 

There  are  reasons  to  believe  that  the  metamorphism  of  this 
series  took  place  at  no  great  depth.  The  rocks  were  often 
crushed  into  a  confused  mass  of  rubble  by  dynamic  action  [see 
above,  page  12],  which  is  often  recemented  bj-  metamorphic 
process.  The  readjustment  of  the  strata  under  pressure  hence 
took  place  largely  through  fracturing,  rather  than  through 
flowage  and  flexure  of  the  rocks,  consequently  they  can  not 
have  been  buried  at  great  depths. 

A  much  later  silicification  process  took  place  attendant  upon 
or  just  prior  to  the  ore  deposition  and  of  a  distinct  character 
from  that  above  mentioned,  in  many  cases  resulting  in  the 
formation  of  a  black  opal  rock.  This  opal  replaces  constitu- 
ents of  the  rock  masses,  particularly  but  not  exclusively  serpen- 
tine. The  opal  is  often  deep  black,  resembling  some  varieties 
of  obsidian,  and  is  accompanied  by  small  amounts  of  crystal- 
line silica,  quartz,  and  chalcedonite — the  name  suggested  by 
Dr.  Becker  [above  cited,  page  390]  for  a  mixture  of  opal  and 
cr>'stalline   silica ;  sometimes  it  contains  a  small  amount  of 


20  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

calcite.  A  perfect  network  of  minute  bands  of  quartz  often 
traverses  the  opal,  resulting  from  infiltration  into  fissured  opal. 
This  material  is  seldom,  if  ever,  free  from  sulphides  of  iron, 
occasionally  of  nickel,  and  at  least  traces  of  cinnabar  are  inva- 
riably found  close  to  it  (hence  its  local  name  of  "quicksilver 
rock"),  showing  its  close  relation  to  metalliferous  solutions. 
While  some  of  this  opaline  rock  has  certainl}-  been  deposited 
in  pre-existing  openings,  a  large  part  is  a  substitution  product. 
The  silica  solutions  seem  to  have  permeated  more  or  less  frac- 
tured rocks,  principally  serpentine,  dissolving  the  bases  and 
depositing  the  opal. 

This  silicification  process  is  closeh'  related  to  the  deposition 
of  cinnabar  ores  and  to  the  later  igneous  phenomena.  As 
above  stated,  cinnabar  is  often  found  in  the  filling  of  minute 
cracks  in  the  opaline  rock,  accompanied  bj'  quartz  and  chal- 
cedonite,  but  seldom  if  ever  imbedded  in  the  opal.  Hence  this 
silicification  process  must  have  preceded  the  ore  deposition; 
but  the  effects  of  the  two  processes  are  so  closeh'  related  that 
the  former  must  have  been  an  earlier  stage  of  the  latter.  The 
fact  that  mercuric  ores  are  hardly  ever  found  in  direct  contact 
with  the  opal  is  hard  to  explain,  as  it  would  suggest  that  the 
siliceous  solutions  during  that  period  of  the  process  were 
entirely  barren  of  mercuric  sulphide.  The  solutions  during  the 
ore  deposition  were,  however,  also  certainl}-  siliceous,  and 
hence  it  is  hard  to  understand  wh}'  the  former  should  have 
been  entirelj'  barren.  Dr.  Becker  ofiers  as  explanation  the 
hypothesis  that  the  cinnabar  was  separated  from  the  solutions 
in  the  fissures  when  the  siliceous  fluids  permeated  the  rocks, 
through  a  mechanical  process  more  or  less  analogous  to  dialysis. 
The  difficulty  is,  however,  that  metallic  salts  are  cr3'stalloid 
bodies  and  pass  readilj'  through  membranes,  while  silica  is 
colloid.  In  the  Manhattan  mine,  Xapa  Count}^  sulphide  of 
mercury-  is,  besides,  found  intimately  mixed  with  the  chalce- 
donite.  This  silicification  process  was  directly  connected  with 
the  later  igneous  eruptions  and  intrusions.  Perhaps  the  greater 
heat  during  the  first  part  of  the  period  covered  by  this  process 
may  ofier  an  explanation  for  the  absence  of  mercuric  sulphide 
in  the  opal  then  formed.  [See,  on  this  point.  Genesis  of  the 
Quicksilver  Deposits,  page  26.] 

Calcite  and  dolomite  form  besides  the  silica  the  gangue  min- 
erals accompanying  the  cinnabar.     Sometimes  these  carbonates 


GEOLOGY   OF   THE    QUICKSILVER    BELT.  21 

are  in  direct  contact  with  the  cinnabar.  The  associated 
metallic  minerals  are  in  nearly  all  cases  pyrite  and  marcasite; 
very  often  arsenious  and  antimonious  minerals,  and  sometimes 
copper  minerals.  Cinnabar  ores  are  nearly  exclusively  depos- 
ited in  pre-existing  openings.  Ore  bodies  precipitated  b}' 
substitution  are  very  rare.  Where  cinnabar  deposition  can 
now  be  observed  the  same  rule  holds  good.  The  later  igneous 
eruptions,  to  which  the  ore  deposition  is  related,  are  of  Tertiary 
or  later  date.  Becker  [above  cited,  page  152  and  following] 
cites  three  different  periods:  The  first,  pre- Pliocene,  during 
which  large  masses  of  andesite  were  ejected — a  bluish-gray 
rock,  containing  pyroxene  and  feldspar  crystals  imbedded  in  a 
ground  mass  of  feldspar  and  magnetite.  A  later  andesitic 
eruption,  very  late  Pliocene  or  at  the  close  thereof;  the  ande- 
sites  belonging  to  a  special  group  having  a  trachytic  character, 
for  which  Becker  proposes  the  name  Asperites.  Rhyolite, 
probably  younger  than  the  andesites,  is  found  near  New  Alma- 
den  and  in  the  northwestern  part  of  San  Luis  Obispo  County. 
Basalt  eruptions,  belonging  to  the  Quaternary  and  more  recent 
periods.  These  eruptions  are  closely  related  to  the  fissure 
system  of  the  former  upheavals,  which  had  established  lines  of 
weakness,  along  which  the  strata  adjusted  themselves  to  the 
posterior  deformations.  The  ore  depositions  were  most  prob- 
ably formed  by  mineral  springs  connected  with  the  volcanic 
activity  of  the  post- Andesitic  period;  hence  the3'  belong  to  the 
post-Pliocene  period.  According  to  Becker,  this  is  indicated 
by  the  usual  association  of  cinnabar  with  basalt,  or  as  in  New 
Almaden  with  rhyolite,  and  also  by  the  unimportance  of  cin- 
nabar deposits  in  andesite.  It  is  a  striking  fact  that  most  of 
the  prominent  mines  north  of  San  Francisco  are  in  close  prox- 
imity to  basaltic  or  relatively  recent  eruptions,  as  for  instance: 
The  .^tna  mines,  a  basalt  dike  on  the  Silver  Bow  claim,  and 
basalt  in  the  Star  claim;  the  Oathill  mine,  a  large  basalt  body 
in  close  vicinity  to  the  mine;  the  Corona  and  Twin  Peaks 
mines,  between  the  basalt  of  Oathill  and  that  of  the  Howell 
Mountains;  the  Great  Western,  a  body  of  basalt  south  and  in 
close  proximity  to  the  mine;  the  Sulphur  Bank,  basalt  all 
around  the  mine;  the  Manhattan,  surrounded  by  basalt  to  the 
east  and  north;  the  Boston,  within  half  a  mile  of  the  basalt  in 
the  Manhattan  ground. 

In   the  southern  field  the  geological  conditions  vary  very 


22  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

much.  In  the  New  Idria  district  no  definitive!}^  post-Tertiarj' 
igneous  rocks  can  be  found,  and  those  rocks  which  show  indi- 
cations of  igneous  origin  are  so  altered  that  it  requires  micro- 
scopic stud}'  of  the  rocks  to  determine  whether  they  are  altered 
eruptives  or  sedimentaries.  In  the  Stayton  district,  the 
country  rock  near  the  ore  deposition  is  prominently  basaltic, 
sometimes  closely  related  to  Becker's  asperites.  In  San  Luis 
Obispo  County,  in  the  Pine  Mountain,  Adelaide,  and  Oceanic 
districts,  the  scattered  exposures  of  igneous  rock  are  of  rhyo- 
lite.  In  Santa  Clara  County  the  only  eruptive  rock  in  the 
neighborhood  of  the  ore  deposits  is  rhyolite. 


ORE  DEPOSITS, 


The  peculiar  characteristics  of  quicksilver,  so  different  from 
those  of  all  other  metals,  render  the  study  of  the  conditions 
governing  the  genesis  of  quicksilver  deposits  an  intricate 
problem;  in  fact,  some  of  the  phenomena  occurring  in  those 
deposits  have  as  yet  not  been  fully  explained. 

Quicksilver  occurs  in  nature  principally  as  a  sulphide, 
occasionally  to  a  small  extent  associated  with  the  native  metal. 
The  compounds  of  mercury  with  chlorine,  selenium,  tellurium 
antimony,  etc.,  are  all  rare  minerals,  and  probably  the  result  of 
secondar}'  concentration. 

Quicksilver  differs  in  many  characteristics  from  gold,  which 
occurs  in  nature  principally  as  native  metal,  though  occasion- 
ally as  a  telluride.  Gold  is  soluble  in  solutions  of  alkaline 
sulphides  and  iodides,  ferric  sulphate,  and  carbonate  of  sodium 
above  200°  C.  Chlorine  is  a  prominent  solvent  of  gold, 
especially  in  desert  regions.  In  whatever  form  gold  may  be 
transported,  it  is  precipitated  either  as  a  telluride,  or  as  metallic 
gold  associated  with  tellurides  and  sulphides;  whether  gold  is 
precipitated  in  nature  as  a  sulphide  is,  as  yet,  uncertain, 
because  the  existence  of  a  sulphide  of  gold  in  nature  has  not 
been  definitely  established.  At  all  events,  this  sulphide  of  gold 
would  be  an  unstable  compound,  while  sulphide  of  mercury  is 
a  very  stable  compound.  These  differences  are  here  presented, 
because  the  fact  that  gold  is  present  in  cinnabar  deposits  has 
been  used  as  a  strong  argument  in  the  discussion  of  the  genesis 
of  those  deposits. 

Quicksilver  also  differs  greatly  from  silver  in  its  chemical 
behavior  toward  other  elements.  The  original  forms  of  silver 
deposits  are,  besides  sulphides,  sulphantimonious  and  sulph- 
arsenious  salts.  In  the  zone  of  oxidation,  silver  occurs  to  some 
extent  in  the  native  state,  but  much  more  commonly  as  a 
chloride,  cerargyrite. 

Mercuric  sulphide  is  not  found  intimately  associated  with 
the  sulphides  of  lead,  zinc,  and  iron,  as  is  the  sulphide  of  silver. 
Sulphide   of   iron   is   often    found   in    contact  with    mercuric 

(23) 


24  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

sulphide,  but  no  mixtures  of  the  sulphides,  like  argentiferous 
galena,  etc.,  have  been  found.  Oxidation  products  of  mercuric 
sulphide,  similar  to  those  of  the  sulphides  of  lead,  zinc,  copper, 
and  iron,  are  also  unknown. 

Quicksilver  dififers  further  materially  from  all  other  metals 
in  its  behavior  toward  heat.  Nearly  all  metals  have  high 
melting  and  boiling  points,  but  mercury  becomes  a  solid  at 
— 39-5°  C.,  and  boils  at  357"  C,  even  vaporizing  to  a  certain 
extent  at  ordinar}-  temperatures. 

Following  is  a  list  of  the  known  quicksilver  ores: 

Amalgam. — A  compound  of  silver  and  mercury,  AgHg  or 
Ag,Hg3. 

Arguerite,  from  Coquimbo,  Chili.     AgioHg. 
Kongsbergite,  from  Norway.     AgisHg. 

Color  silver  white,  in  isometric  crystals  and  massive. 

Ammiolite. — A  compound  of  mercury  containing  antimony 
and  copper,  also  a  little  sulphur  and  iron.  An  earthy  powder; 
color  deep  red  or  scarlet.  Possibly  antimonate  of  copper  mixed 
with  mercuric  sulphide.     Rare. 

Arguerite. — See  Amalgam. 

Barcenite. — Related  to  Ammiolite,  but  contains  no  copper. 
Possibly  antimonate  of  mercury.     Rare. 

Calomel,  or  Horn  Quicksilver. — Mercurous  chloride, 
Hg2Cl2.  Color  light  yellowish  or  gray;  luster  adamantine, 
translucent  or  subtranslucent.  Tough  and  sectile.  Not 
abundant. 

Cinnabar. — Mercuric  sulphide,  RgSorHgiSi-  Color  bright 
red  to  brownish-red  and  brownish-black.  Streak,. scarlet-red. 
Subtransparent  to  nearly  opaque.  Cr^^stals  often  tabular, 
sometimes  acicular;  also  massive  and  in  earthy  coatings. 
Cinnabar  is  the  principal  mercurial  ore. 

Hepatic  Cinnabar^  or  Liver  Ore,  contains  some  carbon 
and  clay;  color  and  streak  brownish. 

Metacinnabarite^  or  black  sulphide  of  mercury,  HgS  or 
HgsSs.  Amorphous,  color  black,  resembling  graphite, 
streak  same  color.  Fracture  like  tetrahedrite.  Recrys- 
tallizes  on  slow  cooling  into  cinnabar. 

CocciNiTE. — Iodide  of  mercury.  Color  red  to  yellow,  some- 
times green  and  greenish-gray.  In  acicular  crystals  or  mas- 
sive.    Rare. 


ORE   DEPOSITS.  25 

CoLORADOiTE. — Telluride  of  mercury,  HgTe.  Color  gray- 
ish-black.    Rare. 

GuADALCAZARiTE. — Sulphide  of  mercury;  closely  allied  to 
metacinnabarite.  Part  of  the  sulphur  is  replaced  by  selenium, 
some  zinc  is  also  present,  although  these  latter  two  metals  are 
probably  no  essential  portions  of  the  mineral.     Rare. 

KoNGSBERGiTE. — See  Amalgam. 

Lehrbachite. — A  combination  of  selenide  of  mercury  and 
of  lead.     Rare. 

Leviglianite. — A  ferriferous  guadalcazarite.     Rare. 

LiviNGSTONiTE. — A  Combination  of  sulphides  of  mercury 
and  antimonium,  HgS,  aSbiS;;.  Color  grayish-black,  generally 
fibrous,  also  massive,  resembling  stibnite.     Rare. 

AIagnolite. — Mercurous  tellurate,  HgTe-;04.     Rare. 

Mercury,  Native. — Occurs  to  some  extent  in  many  quick- 
silver mines,  exceptionally  in  large  quantities,  generally  in  dis- 
seminated fine  globules. 

Metacinnabarite. — See  Cinnabar. 

OnofriTE. — A  sulphide  of  mercury,  wherein  the  sulphur  is 
partly  replaced  by  selenium,  Hg  (S,  Se),  often  associated  with 
tiemanite.     Rare. 

TiEMANiTE. — Selenide  of  mercury,  HgSe.  Color  dark  steel 
gray,  resembling  galena.     Rare. 

TerlinguaiTE. — Oxychloride  of  mercury.     Rare. 

TocORNALiTE. — Iodide  of  silver  and  mercurj'.  Color  pale 
yellow;  granulaf  and  massive.     Rare. 

The  hydrocarbons  Idrialite  and  Aragotite  in  places  carry 
cinnabar.     Rare. 

In  Hungary  a  copper  ore,  consisting  of  sulphides  of  copper, 
iron,  zinc,  mercury,  antimony,  and  arsenic,  is  found,  often  rich 
enough  in  mercury  to  warrant  the  special  extraction  of  that 
metal  as  a  by-product. 

This  list  shows  that  mercury  combines  in  nature  almost 
exclusively  with  sulphur,  which  in  rare  instances  is  partially 
or  totally  replaced  by  its  closely  related  elements,  selenium 
and  tellurium;  and  that  mercury  also,  but  rarely,  combines 
with  the  halogens  chlorine  and  iodine. 

From  a  practical  point  of  view,  sulphide  of  mercury  and 
native  mercury  are  the  only  products  requiring  consideration, 
the  others  being  of  no  commercial  importance. 


GENESIS  OF  QUICKSILVER  ORE  DEPOSITS^ 


The  majority  of  the  geologists  who  have  treated  the  subject 
of  ore  deposits  consider  them,  as  they  exist  to-day  in  situ,  as 
principall)^  the  result  of  precipitation  from  aqueous  solution. 
[See  Genesis  of  Ore  Deposits,  pages  57  and  73,  F.  Posepny; 
ibid.,  page  284,  C.  R.  van  Hise;  ibid.,  page  658,  Prof.  J.  H.  L. 
Vogt,  etc.]  More  especially  in  reference  to  quicksilver  deposits. 
[Monograph  XIII,  U.  S.  Geological  Sur\'ey,  page  416,  G.  F. 
Becker;  x\merican  Journal  of  Science,  vol.  XVII,  3d  series, 
S.  B.  Christ}-;  Genesis  of  Ore  Deposits,  page  596,  W.  Lindgren.] 

A  concise  exposition  of  the  modern  views  of  the  genesis  of  ore 
deposits  is  required  to  explain  the  special  phenomena  obser^-ed 
in  quicksilver  ore  deposits,  and  the  deductions  to  be  derived 
therefrom. 

There  is  no  reason  for  supposing  that  the  heavj-  metals  of 
ore  deposits  come  from  the  enormously  compressed  centro- 
sphere;  hence  the  conclusion  that  the  ore  deposits  are  derived 
from  the  crust  of  the  earth.  Indeed,  a  notable  number  of  ore 
deposits  may  be  referred  to  eruptive  processes  connected,  not 
with  the  heavj-  interior,  but  with  the  crust  of  the  earth,  which 
must  be  regarded  as  being  at  least  50  kilometers  in  thickness. 

This  crust  can  be  divided  into  zones  from  two  different 
standpoints: 

{a)  The  zone  of  fracture. 

The  intermediate  zone  of  combined  fracture  and  flowage. 
The  zone  oi  flowage. 

These  zones  are  delimited  b}-  the  manner  in  which  the  rocks 
j'ield  to  deformation.  In  the  upper  zone  of  fracture,  the  strata 
yield  to  deformation  by  fracturing;  in  the  deepest  zone,  onh* 
spaces  of  microscopic  size  can  exist,  and  the  deformation 
process  is  similar  to  that  of  mashing  or  kneading. 

The  maximum  depth  (assuming  no  lateral  pressures  occur) 
be3''ond  which  the  strongest  rock  material  will  yield  to  defor- 
mation by  flowage  can  be  placed  at  12,000  meters.  In  regions 
of   orogenic   and   eruptive   actions,   the   lateral   stresses   may 

(26) 


GENESIS    OF   QUICKSILVER    ORE    DEPOSITS.  27 

materially  reduce  this  depth,  which  probably  may  have  to  be 
further  reduced,  because  of  the  greatly  increased  plasticity  of 
the  rocks  saturated  with  superheated  water.  It  therefore 
follows  that  all  fissures  must  disappear  at  a  certain  depth. 

As  rocks  are  of  varying  strength,  and  as  lateral  pressures 
materially  influence  the  conditions  under  which  the  rocks 
exist,  there  must  be  a  zone  of  combined  fracture  and  flowage 
below  the  zone  of  fracture.  This  belt  has  a  considerable 
thickness,  possibly  over  5000  meters. 

The  earth  crust  may  also  be  subdivided  from  a  physico- 
chemical  standpoint,  controlled  by  the  relations  between  chem- 
ical action  and  heat  and  pressure,  into: 

(d)  The  Upper  Physico-cJiemical  zone,  resubdivided  into: 
.  Upper  Belt — Belt  of  weathering. 
LrOwer  Belt — Belt  of  cementation. 
The  Lower  Physico-chemical  zone. 

Near  the  surface,  where  temperature  and  pressure  are  low, 
the  preponderating  reactions  are  heat-developing.  In  the 
lower  zone  the  heat-absorbing  reactions  preponderate,  accord- 
ing to  van  Hoff's  law.  [W.  Nernst,  Theoretical  Chemistry, 
page  583.] 

Two  important  reactions  separate  these  zones:  First,  tne 
reactions  between  oxygen  and  sulphur.  In  the  upper  zone 
oxygen  replaces  sulphur,  resulting  in  great  liberation  of  heat 
and  expansion  of  the  volume  of  the  solid  compound.  In  the 
lower  zone  sulphur  replaces  oxygen  with  condensation  and 
great  absorption  of  heat.  This  reaction  is  the  more  important 
when  considering  that  oxide  of  iron,  in  the  form  of  magnetite, 
is  one  of  the  constituents  of  eruptive  rocks  (rocks  of  deep- 
seated  origin).  Secondly,  the  reaction  between  carbon  dioxide 
and  silica.  In  the  upper  zone,  especially  in  the  belt  of  weather- 
ing, carbon  dioxide  replaces  silica,  acting  specially  upon  sili- 
cates; the  liberated  silica  passing  into  solution  in  a  colloidal 
form  and  not  ionized  [Kahlenberg  and  Lincoln,  Journal  of 
Physical  Chemistry,  1898,  page  88],  and  carried  downward  into 
the  belt  of  cementation.  In  the  lower  zone  silica  replaces  car- 
bon dioxide,  with  great  absorption  of  heat  and  with  condensa- 
tion; the  carbon  dioxide  entering  into  the  solution. 

The  depths  at  which  these  reactions  reverse  for  different 
compounds,  and  for  the  same  compound  under  different  con- 


28  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

ditions,  are  very  variable,  and  are  greatly  affected  b\-  the  fact 
whether  the  latter  are  mass-static  or  mass-dynamic. 

The  water  circulation  through  the  earth  crust  represents  a 
cycle,  caused  chiefly  by  gravitation  stress,  and  is  due  to  the 
fact  that  the  water  entering  the  ground  at  a  certain  level,  after 
a  short  or  long  underground  journey,  issues  at  a  lower  level. 

From  the  point  of  view  of  the  genesis  of  ore  deposits,  only 
the  water  that  enters  that  part  of  the  earth  crust  situate  below 
ground-water  level  is  of  importance.  Its  temperature  increases 
with  depth,  and  below  3000  meters,  in  the  zone  of  fracture,  it 
is  in  the  form  of  superheated  water,  having  consequently  great 
chemical  activity. 

There  is  a  strong  tendency  for  water  entering  through  an 
indefinite  number  of  small  openings  to  converge  into  larger 
openings  which  are  located  on  the  lines  of  weakness  in  the 
formations.  These  waters  reach,  in  the  lowest  part  of  their 
course,  where  they  possess  their  highest  chemical  activity,  the 
zone  wherein  sulphur  is  the  more  active  agent,  so  that  they 
dissolve  prominently  sulpho-compounds  out  of  the  rocks, 
through  which  they  percolate  in  capillary  and  supercapillary 
openings,  until  saturated,  and  hold  them  in  solutions  in  ion- 
ized form.  The  precipitation  out  of  these  solutions  is  the 
result  of  supersaturation  due  to  several  causes,  among  which 
the  most  prominent  are  dilution  and  loss  in  temperature  and 
pressure. 

It  is  more  than  probable,  from  the  intimate  association  of 
igneous  rocks  with  a  large  majority  of  ore  deposits,  that  they 
are  the  main  source  of  the  metallic  ores;  and  that  there  is 
a  direct  genetic  relation  between  ore  deposits  and  eruptive 
processes.  A  number  are,  in  fact,  intimately  connected  with 
eruptive  magmas,  especially  through  eruptive  after-action,  as 
sublimation,  gaseous  action,  igneous-aqueous  action,  etc.,  by 
which  the  heavy  metals  were  in  great  part  extracted  from 
such  magmas.  As  the  eruptive  magmas,  at  least  those  of 
deep  origin,  are  admitted  to  contain  a  more  or  less  notable 
admixture  of  water,  with  other  constituents  of  hydrous  or 
gaseous  character,  the  formation  of  minerals  on  cooling  and 
the  subsequent  cycle  of  solution  and  reprecipitation,  as  above 
described,  will  take  place. 

In  this  connection  the  following  quotation  is  important: 
"It  is  thought  highty  probable  that  under  sufficient  pressure 


GENESIS   OF    QUICKSILVER    ORE    DEPOSITS.  29 

"and  at  a  high  temperature  there  are  all  gradations  between 
"heated  water  containing  mineral  material  in  solution  and  a 
"magma  containing  water  in  solution.  If  this  be  so,  there 
"also  will  be  all  stages  of  gradation  between  true  igneous 
"injection  and  aqueous  cementation,  and  all  the  various  phases 
"of  pegmatization  may  thus  be  fulh'  explained."  [C.  R.  van 
Hise,  1 6th  Ann.  Rep.,  vol.  XI,  page  647.] 

The  foregoing  explains  the  reason  that  the  metals  are  origi- 
nally deposited  principally  in  the  form  of  sulpho-compounds; 
which,  in  the  upper  portion  of  the  earth  crust,  in  the  belt  of ' 
weathering,  under  the  action  of  the  various  gases,  especially 
carbon  dioxide  and  oxygen,  and  of  organic  bodies,  are  trans- 
formed into  various  oxidation  products  thereof,  including  the 
native  metal.  [See  on  this  subject  more  particularly:  F, 
Posepny,  Genesis  of  Ore  Deposits;  C.  R.  van  Hise,  Principles 
of  North  American  Pre-Cambrian  Geolog}',  i6th  Ann.  Rep. 
U.  S.  Geological  Sun'e}^  Pt.  I;  ibid.^  Physico-Chemistry  of 
Metamorphism,  Bulletin  Geol.  Soc.  of  Am.,  vol.  IX;  J.  L.  H. 
Vogt,  Problems  in  the  Geology  of  Ore  Deposits,  Genesis  of 
Ore  Deposits,  page  636  and  following;  etc.] 

The  opinion  that  quicksilver  deposits  are  formed  in  accord- 
ance with  the  general  principles  above  described  is  based  upon 
obser\^ations  at  Steamboat  Springs  and  Sulphur  Bank,  and 
finds  confirmation  in  the  associated  minerals  within  those 
deposits  which  bear  evidence  of  precipitation  out  of  aqueous 
solutions.  The  following  observations  on  this  subject  are  of 
sufficient  importance  to  be  shortly  discussed: 

Most  of  these  deposits  show  that  at  some  time  during  their 
history  they  have  been  the  scene  of  intense  solfataric  action, 
and  a  great  many  are  in  contact  or  in  close  proximity  to 
eruptive  phenomena. 

Mercury  boils  at  357*^  C,  but  volatilizes  to  some  extent  at 
ordinary  temperatures. 

Liquid  mercury  combines  with  sulphur  in  the  manufacture 
of  vermilion  in  the  dry  way,  below  the  melting  point  of  sul- 
phur, 120°  C. ;  in  the  wet  waj',  sulphide  of  mercury  forms 
between  45°  and  50°  C.  Hence  the  combination  of  mercury 
and  sulphur  takes  place  between  liquid  mercury  and  sulphur. 
That  in  the  wet  process  a  heat  below  50°  C.  is  insisted  upon 
would  indicate  that  the  combination  of  liquid  mercury  and 
sulphur  can  only  take  place  within  the  immediate  vicinity  of 


30  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

the  surface,  as  the  proximity  of  igneous-aqueous  action  to  the 
quicksilver  deposits  during  some  time  of  their  history  will 
cause  the  increase  of  heat  in  depth  to  be  much  more  rapid  than 
the  ordinary  static  rate  of  i°  C.  per  loo  feet.  (At  Sulphur 
Bank,  Dr.  Becker  gives  the  heat  of  the  water  of  the  Herman 
shaft  at  the  surface  128°  F.,  and  at  a  depth  of  300  feet  176°  F.) 

In  vapor  form  mercury  combines  with  sulphur  at  high  tem- 
peratures, proof  of  which  can  be  found  in  the  bricks  of  old 
furnaces  wherein  cinnabar  and  native  mercury  are  often  found 
in  large  quantities;  the  mercurial  vapors  must  have  recombined 
with  free  sulphur  in  vapor  form  and  recr^'stallized  as  cinnabar. 
The  agency  which  causes  the  recombination  of  these  disso- 
ciated vapors,  at  practically  the  same  temperature,  is  as  yet 
undetermined. 

All  these  considerations  have  caused  a  great  number  of 
operators  of  quicksilver  mines  to  retain  the  old  theory  of  ore 
formation  by  sublimation,  and  to  hold  the  opinion  that  mer- 
cury is  brought  into  the  lithosphere,  and  possibh'  even  into  the 
belt  of  weathering,  in  the  form  of  mercurial  vapors.  These, 
under  favorable  conditions,  form  mercuric  sulphide,  which  then 
follows  the  cycle  of  solution  and  precipitation  indicated  by 
Messrs.  Becker  and  Christy,  namely,  a  solution  of  a  double 
sulphide  of  mercury  and  sodium  (HgS,  nNaiS)  in  waters  holding 
in  solution:  alkaline-sulphides,  -sulph5'drates,  and  -h3-drates, 
or  neutral  or  acid  sodium  carbonates  partially  saturated  by 
hydrogen  sulphide;  and  a  precipitation  mainly  due  to  decrease 
in  temperature  and  pressure  or  to  dilution. 

Dr.  Becker  [Mon.  XIII,  U.  S.  G.  S.,  above  cited,  page  419 
and  following]  thoroughly  discusses  this  subject  and  gives 
extensively  his  reasons  for  considering  the  cinnabar  deposits  as 
exclusively  formed  by  precipitation  from  solutions.  Prof.  S.  B. 
Christy  [Am.  Journal  of  Science,  vol.  XVII,  3d  series,  1879,  page 
453  and  following]  had  previously  given  his  reasons  why  he 
arrived  at  the  same  conclusion.  He  made  several  tests  as  to 
the  solubility  of  mercuric  sulphide  in  different  solutions  under 
varying  conditions  of  temperature  and  pressure,  and  regarding 
its  precipitation  out  of  those  solutions.  A  short  extract  from 
his  article  will  be  of  great  interest: 

"The  tests  were  made  at  temperatures  varying  from  200"^'  to 
"250°  C,  and  pressures  varying  from  260  to  500  pounds  per 


GENESIS   OF   QUICKSILVER    ORE    DEPOSITS.  31 

"  square  inch.  The  duration  of  the  tests  varied  from  three  to  ten 
"hours,  and  in  each  case  the  cooling  was  allowed  to  take  place 
"gradually  and  undisturbed.  Their  result  proved  that  waters 
"containing  solutions  of  alkali  sulphides  and  some  natural  min- 
"eral  waters  to  which  sulphydric  acid  had  been  added,  will, 
"under  certain  conditions  of  temperature  and  pressure,  dissolve 
"mercuric  sulphide;  that  increase  in  pressure  aids  rather  than 
"retards  this  solution,  and  that  cinnabar  is  deposited  from  such 
"solutions  in  the  crystallized  form  when  temperature  and  pres- 
"sure  are  slowly  lowered,  while  the  occasional  occurrence  of 
"  metacinnabarite,  or  black  amorphous  sulphide  of  mercury,  was 
"explained  by  the  sudden  dilution  or  cooling  of  the  depositing 
"waters,  or  the  local  mixing,  during  crystallization,  of  agents 
"causing  rapid  precipitation." 

Professor  Christy  in  the  course  of  these  tests  obtained  out  of 
a  solution  of  potassic  sulphydrate  wherein  amorphous  mer- 
curic sulphide  was  placed,  a  coherent  mass  of  crystals  of  cinna- 
bar, perfectly  simulating  the  crystals  which  occur  in  nature. 
He  further  argues  that  while  the  deposition  of  cinnabar  from 
mercury  in  vapor  form  occurs  in  the  masonry  of  furnaces, 
condenser  walls,  etc.,  the  same  can  not  account  for  the  same 
action  in  ore  deposits,  because  the  high  temperature  required 
to  volatilize  mercury  and  cinnabar  would  destroy  the  gangue 
minerals  almost  invariably  associated  with  the  ore  in  nature, 
such  as  dolomite,  calcite,  bitumen,  and  pyrites,  which  besides 
are  never  found  in  the  occurrences  of  cinnabar  and  mercury  in 
the  masonr}^  of  furnaces  and  condenser  walls,  directly  traceable 
to  volatilization  and  sublimation. 

There  are  some  fundamental  differences  between  quicksilver 
ore  and  gold  ore  deposits,  which  must  be  noted.  All  the  quick- 
silver deposits  worked  up  to  the  present  time  show  a  lack  of 
persistence  in  depth,  and  at  a  rather  shallow  depth  in  the 
different  deposits  their  cinnabar  content  becomes  too  low  for 
commercial  purposes.  The  approach  of  this  impoverishment 
is  in  nearly  every  case  accompanied  with  the  occurrence  of 
native  mercury,  while  in  gold  deposits  generally,  once  the 
sulphide  zone  is  reached,  the  character  of  the  ore  remains 
nearly  permanent. 

Dr.  Becker  attributes  this  phenomenon  to  the  precipitation 
of  native  mercury  by  dilution  of  the  solution,  or  by  the  action 
of  decomposition  products  of  organic  matter;  the  latter  causing 


32  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

the  presence  of  hydrocarbons  so  often  found  accompanying 
quicksilver  ores.  [Mon.  XIII,  U.  S.  G.  S.,  page  437.]  That 
the  native  mercury  is  mainly  found  in  the  lower  parts  of  the 
mines  is  ascribed  by  him  to  the  fluidit}'  and  high  density  of 
the  metal.      [Ibid.,  page  388.] 

As  to  the  precipitation  of  native  mercury  b}-  dilution,  when 
the  precipitation  is  caused  suddenly,  the  product  is  a  black 
mass  of  metacinnabarite  with  a  very  small  quantity  of  native 
mercury  [ibid.,  pages  429,  430,  and  436]  ;  hence  the  copresence 
of  cinnabar  and  native  mercury  would  involve  a  re-solution 
and  precipitation  and  slow  cooling  of  the  metacinnabarite 
without  affecting  the  native  mercun-  present. 

The  reduction  of  mercuric  sulphide  through  decomposition 
products  of  organic  matter  would  relegate  the  locus  of  this 
reaction  to  the  upper  portion  of  the  deposit,  and  as  those  agents 
are  active  at  the  present  time,  native  mercury  ought  to  be 
found,  at  least  to  some  extent,  in  the  upper  horizon  of  all 
quicksilver  deposits. 

Prof.  S.  B.  Christy  remarks  on  the  occurrence  of  native 
mercury:  "Unless  w^e  regard  it  as  an  efiect  of  local  oxidation 
"of  a  very  stable  compound,  its  appearance  is  well  nigh  inex- 
"plicable  upon  either  h3'pothesis"  of  production  by  sublimation 
or  deposition  from  solution.  [Am.  Journal  of  Science,  vol. 
XVII,  3d  series,  page  463.] 

The  oxidation  of  mercuric  sulphide  takes  place  at  high 
temperature;  mercuric  sulphate  being  formed  in  the  condensers 
nearest  the  furnaces,  but  not  having  been  found  in  nature. 

Whatever  may  be  the  cause  of  the  formation  of  native 
mercurs',  its  fluidity  and  density  can  hardly  account  for  all 
phenomena  of  its  occurrence.  In  the  Socrates  mine,  Sonoma 
County,  native  mercury  is  found  in  fine  globules  within  com- 
pact rock,  while  in  the  fracture  planes  of  the  same  rock  cinnabar 
is  found  associated  with  the  native  metal;  if  the  cinnabar  was 
the  original  form  wherein  the  metal  was  deposited,  some  traces 
of  it  ought  to  be  found  in  the  compact  rock,  where  the  decom- 
posing agents  can  not  have  been  as  active  as  in  the  fracture 
planes.  Original  deposition  as  native  metal  and  subsequent 
transformation  into  sulphide  appear  here  more  probable. 

The  quicksilver  deposits  are  closely  connected  with  eruptive 
phenomena — either  the  presence  of  eruptives,  or  intense  solfa- 
taric  action.     As  Professor  Vogt  states:     "In  the  exceedingly 


GENESIS   OF   QUICKSILVER    ORE    DEPOSITS.  33 

"numerous  deposits  in  some  way  connected  with  eruptive 
"processes,  the  nearness  of  igneous  rocks  must  have  caused 
"increase  of  temperature  (and  also  of  pressure?).  This  is 
"often  so  great  as  to  exceed  for  heavy  compounds  the  critical 
"temperature."     [Genesis  of  Ore  Deposits,  page  659.] 

The  source  of  the  great  heat  in  most  of  the  quicksilver 
mines  can,  in  many  cases,  be  traced  directly  to  the  chemical 
reactions  taking  place  at  the  present  time.  Chemical  activity 
being  increased  by  temperature  and  pressure,  it  is  only  reason- 
able to  suppose  that,  at  no  great  depth,  conditions  exist  which 
would  keep  the  mercury  in  a  gaseous  state. 

The  suggestion  of  Professor  Vogt:  "  With  regard  to  younger 
"veins  especially,  we  must  keep  in  mind  a  possible  extraction 
"from  laccolitic  magma  in  depth"  [ibid.,  page  656],  may 
in  many  cases  offer  an  explanation  for  the  genesis  of  quick- 
silver deposits,  where  no  extrusive  igneous  rocks  are  found  in 
their  vicinity.  Erosion  is  the  cause  of  the  absence  of  quick- 
silver deposits  in  older  formations.  This  erosion  is  much  more 
considerable  than  generall)-  taken  into  account.  [See  ibid., 
page  670.]  Professor  de  Launay,  comparing  ore  deposits  oc- 
curring relativel}-  near  the  surface  in  less  denuded  regions  with 
those  deep  below  the  surface  in  strongly  denuded  regions,  takes 
as  instance  of  the  former  quicksilver  deposits,  "which  occur 
"chiefly  in  recent  rocks  near  volcanic  eruptives,  while  from 
"older  ranges,  partly  destroyed  by  erosion,  they  have  disap- 
"peared  with  other  debris." 

The  cinnabar  deposits  are  in  many  cases  connected  with 
alteration  zones  in  the  country  rock,  caused  by  silicification, 
forming  by  preference  in  those  zones.  The  latter,  however,  do 
not  uniformly  contain  cinnabar,  and  the  same  form  of  altera- 
tion of  the  rocks  is  found  throughout  the  Neocomian  outside 
of  the  quicksilver  belts.  This  process  of  silicification  is  more 
especially  characteristic  of  the  belt  of  cementation.  [See  above, 
page  27.]  The  term  cementation  designates  the  binding  to- 
gether of  the  rock  particles  by  infiltration  of  mineral  materials 
in  solution,  and  their  deposition  as  minerals  in  the  interstices 
of  the  rocks. 

The  process  of  serpentinization  resembles  that  of  silicifica- 
tion. The  material  for  the  serpentine  may  be  furnished 
partly,  or  in  whole,  b}-  the  minerals  present  in  basic  sedimen- 

3— QR 


34  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

tary  rocks,  which  are  altered  through  this  process,  or  the 
material  may  come  from  extraneous  sources.  [Van  Hise,  i6th 
Ann.  Rep.,  Part  I,  page  691.] 

As  serpentine  may  replace  quartz,  the  presence  of  cemented 
and  indurated  sandstones,  chalcedonite,  phthanite,  and  serpen- 
tine may  represent  various  phases  of  the  physico-chemical 
process  of  cementation  in  the  belt  of  fracture. 

This  silicification  process  forms  different  materials  in  different 
localities.  It  forms  a  great  quantity  of  black  opal,  containing 
some  quartz  and  chalcedonite  (a  mixture  of  opal  and  crystal- 
line silica).  A  considerable  portion  of  the  sandstones  of  the 
Coast  Ranges  show  the  effects  of  this  silicification  process,  in 
varying  degrees. 

The  cinnabar  forms  in  the  cracks,  seams,  and  fissures  of  the 
silicified  material.  The  richness  of  the  cinnabar  ore  is  to  a 
great  extent  dependent  upon  the  size  of  the  cavities  favorable 
for  deposition  and  consequently  upon  the  compactness  of  the 
fissure-filling;  hence  rich  ore  bodies  are  principally  found  in 
those  parts  where  the  fissure-filling  has  been  crushed  and 
distorted. 


COST  OF  MINING  AND  REDUCTION. 


The  cost  of  mining  and  reduction  of  quicksilver  ores  differs 
very  sensibly  in  the  various  mines.  The  nature  of  the  ground 
is  one  great  cause  of  this  difference.  In  some  mines  the 
ground  is  such  that  little  or  no  timbering  is  required.  In 
others,  the  ground  is  so  bad  that  the  stopes  have  to  be  tim- 
bered and  filled.  In  some  mines  the  air  is  generally  good, 
while  in  others  the  heat  is  so  great  that  the  men  work  under 
disadvantage. 

The  cost  of  timber  and  cordwood  also  varies  very  much,  some 
districts  being  well  provided  with  timber,  while  others  are  at 
considerable  distance  from  the  source  of  suppl)-. 


'•  I--?/ 


YTVTJOO 


Geology  by  Win.  Forstner,  E.M. 


MAYACMAS    D 


I — Sunrise.  ")  lo — Geyser,  Sulphur, 

2 — Cloverdale.  Il — Black  Bear  Group. 

3— Mercury.  12— Pluton  Den. 

4 — Manzanita.  j  13 — Clyde. 

5 — Albian.  /■  Cloverdale  Mine.  14 — Culver — Baer  Group. 

6 — Mattole.  15— Rattlesnake. 

7 — Mount  Vernon.  16 — Tunnel  Site.    ) 

8 — Philadelphia.  17 — Incandescent.  '- 

9 — Waterloo.  J  18 — Almaden.         ) 


No.                 Name  OF  Mine. 

NO.                          N.4ME  OK  MINE. 

19— Mate.                             1 

29 — Socrates. 

20 — Eureka  Nos.  i  and  2.  [Eureka  Con. 

30 — Mercury. 

21— Captain.                         f 

31— Great  Northern. 

22-                                         1 
23 — Cedar. 

32-Hope.j.  p^„^,,,  p^^i,,^  ^ 

24— Quicksilver.     (    Crown  Point 

34-Denver. 

25— Queen  Group.!            Q.  Mining  Co. 

35-) 

26 — Lookout.   1 

36 — V  Lucky  Stone  Group 

27 — Diamond.  \ 

37—) 

28 — Mercury. 

38— Hurley. 

N.AaiE  OF  Mi: 


39 — Pacific. 

40 — Hercules. 

41 — Sonoma. 

42— 

43— 

44— 

45 — Pontiac. 

46-        " 

47 — Boston. 

48— Empire. 


rn  Point  Quick- 
ver  Mining  Co. 


49 — Double  Star. 

50 — Occidental. 

51 — Healdsburg. 

52— Edith. 

53— Cinnabar  King  Group. 

54-Eugenie.  ) 

55— Maud.       [■  Bacon  Con. 

56— Dragon.    ' 

57— Napa. 


DISTRICT. 


58— St.  George,      i 

59— Golden  Gate.  ■  Bacon  Con. 

60— Eagle.  \ 

61— Helen. 

62 — Young  America. 

63 — Chicago. 

64— Wall  Street. 

65 — ^Jewess. 

66 — Middletown. 

67- 


Nameof  mi: 


68— Gem. 

69 — Great  Eastern. 

70 — Hope. 

71 — Iviverpool  Con. 

72 — Eureka  Con.  ) 

73—       " 


Great  Western 


-Standard  Q.  Co.  5 


74- 
75— 
76- 


1- Napa  Consolidated. 


1 — Eureka  Con. 

79—  " 

80—  " 
I— Contention. 

82  -  Minnesota. 
83 — Manzanita. 
S4 — Mercury. 
S5 — Bone. 
86 — Fanny. 


Napa  Consolidated. 


88— South  Side.' 

89 — Corona. 

90 — Napa  Con. 

91— 

92 — Beecher. 

93 — New  Granada 

94— Twin  Peak. 

95-     " 


Xi..  Namk  of  Mink. 

96 — Ida  Easly. 

97— Old  Discovery. 

98— Twin  Quartz. 

99— Good  Enough. 
100 — Silver  Bow.  ') 
loi— Phrenix.  j 

102— Red  Hill.  [  :jj(^jj  ^^Q„ 

103— Starr.  j 

104— Pope.  I 

(05 — Washington.  J 


34 

tary  rockj 
material  n 
Ann.  Rep. 

As  serp( 
and  indurj 
tine   may 
process  of 

This  sili 
localities, 
some  quar 
line  silica) 
Coast  Ran 
varying  de 

The  cini 
silicified  n 
great  exte: 
for  deposit 
fissure-filli 
those  part 
distorted. 


qAK  J 


rri-  'Tj 


./d/iHOTlIJAO 


COS 


The  cost 
ver>'  sensil 
is  one  gn 
ground  is 
others,  the 
bered  and 
while  in  ot 
disadvanta 

The  cost 
districts  be 
considerab 


A    3TATe 


-  c.tW3J 
Obi 


•ej3»*.«  - 


i 


DISTRICTS    NORTH    OF    SAN  FRANQSCO. 


MAYACMAS  DISTRICT, 

The  Mayacmas  District,  as  defined  b}-  Dr.  G.  Becker  [see 
Mon.  XIII,  U.  S.  G.  S.,  page  368],  embraces  parts  of  Napa, 
Lake,  and  Sonoma  counties,  along  the  Mayacmas  range,  of 
which  Mount  St.  Helena  and  Mount  Cobb  are  the  most  promi- 
nent mountains.  [See  geological  map  of  portions  of  Napa, 
Sonoma,  and  Lake  counties  quicksilver  districts,  in  this  Bul- 
letin.] 

Quicksilver  deposits  are  found  on  both  sides  of  the  range; 
the  main  belt,  however,  lies  in  its  eastern  part  north  of  the  range, 
crosses  it  near  Pine  ^Mountain  (between  Mount  St.  Helena  and 
Mount  Cobb),  and  lies  principally  south  of  it,  west  of  Pine 
Mountain  in  Sonoma  County. 

The  general  trend  of  the  belt  is  northwest.  In  its  south- 
eastern part,  in  Napa  Count3',  it  is  in  very  close  proximity  to 
a  region  of  very  intense  and  probably  prolonged  eruptive 
action,  covering  Tertiarj-  and  post-Tertiary  periods.  The 
center  of  eruptions  in  this  region  was  probably'  in  the  territory 
bounded  b}-  Mount  St.  Helena,  the  Twin  Peaks  (or  Sugar 
Loafs),  and  High  Peak;  the  flows  have,  however,  spread  over 
a  large  adjoining  territory.  Outside  of  this  are  found  a  great 
many  other  eruptive  bodies  in  this  district,  of  which  the  more 
prominent  are:  The  basalt  body  on  Oathill,  some  smaller 
ones  in  the  territory  of  the  ^-Etna  Consolidated  Company,  an 
andesitic  eruptive  body  northeast  of  Oathill,  Pine  Mountain, 
Col)b  Mountain,  and  others.  This  district  is  hence  a  region  of 
intense  eruptive  action.  Large  masses  of  lava  have  covered 
parts  of  it,  and  while  partly  eroded,  extensive  sheets  of  tufa 
cover  at  present  parts  of  it  to  a  greater  or  less  depth,  and  make 
it  ver>-  difficult  to  determine  the  limits  of  the  cores  of  igneous 
rocks.  The  present  deeply  car\-ed  topography  of  the  region  is 
largely  governed  by  the  erosion  of  this  capping. 

The  older  rocks  are  mainly  represented  by  sandstones,  some- 
times   nearly    unaltered,    sometimes    thoroughly    altered    into 

(35) 


36  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

schists,  with  all  intermediary  gradations.  Serpentine  is  very 
prominent,  mostly  a  hard,  dry  variety,  in  places  disintegrated 
and  pulverized  b}-  weathering,  showing  as  large  bare  spots 
along  the  ranges.  Even  where  not  bare,  the  serpentine  can  be 
detected  at  a  distance  by  a  sparse  vegetation,  w^hile  on  the 
balance  of  the  surface  a  ver>'  close  growth  of  brush  or  grass  is 
found.  The  relation  of  the  serpentine  to  the  quicksilver 
deposits  is  not  clear.  Most  of  these  are  associated  with,  or  in 
close  proximity  to,  serpentine;  but  others,  like  those  at  Oat- 
hill  and  Cloverdale,  are  entirel}'  away  from  the  serpentine; 
and  where  the  serpentine  is  verj^  prominent  and  continuous 
over  a  certain  width,  no  deposits  of  any  value  have  been  found; 
as,  for  instance:  between  Oathill  and  the  Mirabel  around  the 
head  of  Bucksnorter  Creek;  on  the  ridge  between  Bear  Creek 
and  Drj'  Creek ;  on  the  main  ridge  between  the  headwaters  of 
Dry  Creek  and  Briggs  Creek.  Neither  are  workable  quick- 
silver deposits  found  in  the  serpentine.  Where  serpentine  is 
associated  with  any  deposits,  these  are  always  contact  deposits, 
while  both  the  Oathill  and  Cloverdale  mines  are  in  the  sand- 
stone. 

The  quicksilver  deposits  appear  from  their  association  with 
the  opaline  rock,  which  is  presumably  an  alteration  product  of 
serpentine  by  silicification,  to  be  related  to  the  serpentine  to 
a  certain  extent.  The  fact  that,  where  it  is  A-ery  wide,  no 
paying  deposits  have  been  found,  would  indicate,  however, 
that  either  the  sandstones  contain  the  primary  disseminated 
metal,  which  is  concentrated  through  some  process  of  second- 
ary concentration,  or  else  in  the  large  bodies  of  serpentine  the 
concentration  took  place  only  in  those  parts  affected  by  contact 
metamorphism.  While  this  holds  true  only  for  the  south- 
eastern part  of  the  district,  it  must  be  remarked  that  in  the 
northwestern  part,  in  Dry  Creek  and  Pine  Flat  districts,  there  is 
in  many  cases  an  undoubted  relation  between  the  quicksilver 
occurrence  and  igneous  actions.  In  the  Dry  Creek  district  the 
only  deposit  of  any  ascertained  consequence  is  the  Helen, 
which  lies  very  close  to  the  tufas  of  Pine  Mountain.  There 
are  undoubted  signs  of  igneous  rocks  in  the  Pine  Flat  district 
on  both  sides  of  Big  Sulphur  Creek;  some  of  these  igneous 
dikes  run,  as  far  as  determined,  in  a  direction  which  would 
bring  them  near  the  ore  deposits  of  the  Eureka  mine;  others 
were  found  near  the  Cloverdale  mine.     For  a  great  number  of 


MAYACMAS    DISTRICT.  oi 

deposits,  these  relations  are  not  yet  determined.  Considering 
the  intimate  relation  of  quicksilver  deposits  and  aqueo-igneous 
actions  and  the  general  geological  conditions  in  this  region,  it 
may,  however,  be  expected  that,  at  least,  laccolitic  relations 
exist  there. 

Between  the  Corona  and  St.  Helena  Creek,  a  distance  of 
four  miles  in  an  air  line,  along  the  headwaters  of  Bucksnorter 
Creek,  the  belt  of  serpentine  is  verj-  wide.  Between  St.  Helena 
Creek  and  Bucksnorter  Creek  the  Standard  Quicksilver  Min- 
ing Company-  has  in  the  last  few  years  spent  a  considerable 
sum  of  money  prospecting,  but  so  far  without  any  favorable 
result. 

To  the  west  of  the  Great  Western  mine  are  the  headwaters 
of  Dry  Creek,  a  bowl-form  basin  nearly  encircled  bj'  the  main 
ridge  and  by  a  ridge  dividing  Dry  Creek  from  the  drainage  of 
Putah  Creek.  Serpentine  is  very  prominent  in  a  great  portion 
of  the  Dry  Creek  basin,  and  again  barren  of  any  workable 
deposits  of  cinnabar,  notwithstanding  some  very  prominent, 
peculiar  croppings,  standing  out  boldly  in  the  serpentine. 
These  croppings,  especially  prominent  in  the  Wall  Street  and 
Jewess  grounds,  consist  of  a  network  of  white  quartz  seams, 
mostly  thin  amorph  quartz,  with  occasional  concretions  of 
botryoidal  form;  the  ground  mass  is  a  light  yellow-brown, 
ochreous  mass;  this  material  is  locall}-  called  "dry  bone,"  and 
so  far  as  yet  observ'ed,  never  indicates  a  w^orkable  ore  deposit. 
The  same  is  found  on  the  Bacon  Consolidated  and  Cinnabar 
King  ground  (Pine  Mountain),  and  also  in  the  Double  Star 
mine  (Pine  Flat).     (Lawson's  silica-carbonate  sinter.) 

Pine  Mountain  is  a  mass  of  andesitic  tufa,  most  probably 
with  an  eruptive  core,  of  small  dimensions  and  very  steep 
sides,  and  entirely  disconnected  from  the  Mount  St.  Helena 
and  the  Mount  Cobb  groups  of  eruptives.  Its  main  ridge  is 
not  over  25  feet  wdde,  and  about  300  feet  long;  elevation,  3475 
feet.  The  tufa  is  of  a  light  grayish  color,  and  has  spread  over 
a  part  of  the  adjacent  ravines.  No  signs  of  basaltic  rock  could 
be  found  on  the  ridge.  The  Helen  mine  is  situated  on  the 
eastern  slope,  near  the  edge  of  the  tufa,  and  on  the  south- 
western, western,  and  northwestern  slopes  are  located  a  series 
of  mines,  comprising  the  Cinnabar  King  and  Bacon  group  of 
mines.  The  northwestern  slope  is  very  steep  and  partly  cov- 
ered by  tufa,  which  covers  alternate  beds  of   serpentine  and 


38 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


Fig.  I.     Section  of  uonhwest  slope  of  Pine 
Mountain,  Sonoma  County. 


metamorphosed  sandstones.  At  the  contacts  wide  belts  of 
croppings  show,  partly  in  place,  partly  covering  the  side  hill 
with  large  bowlders.  These  croppings  resemble  very  much 
those  of  the  Wall  Street  and  Jewess.  In  the  caiion  continu- 
ing below  the  old  road  from  Middletown  to  Pine  Flat  a  very 
well-defined  cropping  on  the  contact  of  serpentine  and  sand- 
stone is    seen.     [See  Fig.   i.]     A  great  amount  of  work  has 

been  done  here;  remnants 
of  old  shafts  and  tunnels 
are  found  everywhere  on 
the  hillsides,  but  all  work 
is  now  abandoned.  Sev- 
eral pockets  of  very  rich 
cinnabar  ore  were  found 
at  diSerent  points  at  the 
surface,  but  none  appear 
to  have  been  found  persist- 
ent in  depth. 

The  headwaters  of  Putah  Creek  are  situated  in  a  basin  on 
the  south  slope  of  Mount  Cobb.  In  this  basin  are  a  great 
number  of  hot  springs,  of  which  Anderson  Springs  are  by  far 
the  most  prominent.  These  springs  generally  contain  a  great 
amount  of  sulphur,  and  in  several  places  sulphur  deposition 
and  rock  decomposition  b}-  sulphurous  fumes  are  taking  place. 
Here,  as  in  other  parts  of  the  district,  cinnabar  deposition 
does  not  occur  in  or  close  to  those  places  where  hot  waters  and 
vapors  reach  the  surface.  There  are  no  cinnabar  mines  in  this 
basin — only  a  few  prospects,  which  can  scarcely  be  said  to 
give,  up  to  the  present,  much  promise  of  turning  into  mines; 
a  condition  partly  due  to  insufficient  development. 

The  mines  around  Mount  St.  Helena  have  a  considerable 
supply  of  timber  in  their  vicinity,  although  the  ^Etna,  Oathill, 
Corona,  Mirabel,  and  Great  Western  mines  have  made  serious 
inroads  on  the  supply.  The  Oathill  mine  is  the  only  one  having 
a  sawmill.  The  other  mines  must  use  round  timbers,  or  get 
their  timbers  from  the  sawmills  in  Lake  County  at  the  foot  of 
Mount  Cobb.  In  the  Pine  Flat  district,  the  timber  supply  is 
rather  scant.  There  is  one  sawmill  in  the  district.  Round 
timbers  cost  per  set,  including  lagging,  from  $2.50  to  $2.75; 
timbers,  7  cents   per  linear  foot;    lagging,  3^   cents   apiece; 


-TT- 


An 


i^' 


r^ 


v., 


f^. 


.-J- 


^^Sr 


5-y 


V?      ^ 


L\ 


''K^, 


\\jO\v4v  Lake 


\         /^hur»lpi(Lake 


\<M 


C  0 y  o  t  *         ^i>  Gehnatdl  lake 


,Y<i' 


j% 


wjii  1  r ' 


-/'• 


-^^^^iii^ 


''^^^^^-^r:^"' 


[IZl      [Z] 


GEOLOGICAL    MAP    OF    NAPA,    SONOMA,    LAKE,    AND    YOLO    COUNTY    QUICKSILVER    DISTRICTS, 

IssuKD    BV    California    Statu    Mining    Bureau— Lewis    E.    Auburv,    Statu    Minbralouist,    1903. 


CLEAR    LAKE    DISTRICT.  39 

sawed  square  sets  at  mill,  $2.15;  lagging,  15  at  7  cents,  $1.05; 
cordwood  averages  from  S2.50  to  $3  per  cord. 

This  district  connects  by  several  good  roads  with  railroads. 
The  southeastern  and  central  parts,  by  three  roads  to  Calistoga — 
one  from  Oathill,  the  toll  road  from  Middletown,  and  the  toll 
road  from  the  Great  Western  mine;  distances,  from  12  to  20 
miles.  The  northwestern  part  connects  with  Calistoga  and 
Healdsburg,  and  for  the  most  extreme  northwestern  portion 
also  with  Cloverdale;  distances,  from  16  to  20  miles. 

CLEAR  LAKE  DISTRICT. 

The  southern  borders  of  Clear  Lake  and  the  adjoining  terri- 
tory* have  been  a  region  of  great  volcanic  activity;  a  great 
part  of  the  territory  south,  southeast,  and  east  of  Clear  Lake 
bears  evidence  of  having  at  one  time  been  covered  by  lava 
flows,  most  of  the  ridges  being  covered  with  eruptive 
flows.  [See  Report  State  Mining  Bureau  of  Cal.,  X,  page  232.] 
Whether  these  were  ejected  from  a  few  large  vents,  or  from  a 
great  number  of  disseminated  minor  vents,  has  not  yet  been 
determined.  In  close  proximit}'  to  Clear  Lake,  at  Mount  Ko- 
nockti  or  Uncle  Sam,  and  in  the  territory  northwest  of  Sulphur 
Bank,  such  vents  are  undoubtedly  located.  These  eruptions 
took  place  at  different  periods,  and  ejected  lavas  of  different 
compositions.  Mount  Konockti  is  formed  b)-  later  andesites, 
which  are  also  found  to  the  northeast  of  the  lower  part  of  Clear 
Lake;  but  in  the  close  neighborhood  of  Sulphur  Bank  the 
eruptives  are  priiicipall}^  but  not  exclusively,  basalts.  These 
latter  eruptions  must  have  been  recent,  the  basalt  overlying 
the  Quaternary  Cache  Lake  beds.  To  the  northeast  of  the 
lava  flows  in  this  district  is  a  verj*  extensive  belt  of  serpentine; 
but  the  rocks  underlying  the  lava  flows  are,  north  of  Putah 
Creek,  prominently  sandstones  and  shales.  [See  geological 
map  of  Napa,  Sonoma,  Lake,  and  Yolo  counties  quicksilver 
deposits.] 

Around  Lower  Lake  lumber  is  worlh  $17  per  1000  feet 
(B.  M.);  round  timber,  6  cents  per  linear  foot;  lagging,  6  cents 
apiece. 

This  district  finds  its  railroad  outlet  through  Calistoga. 
Lower  Lake  is  33  miles  distant  from  that  town. 


'-5-^- 


..-^ 


i^v^, 


f^ 


CLEAR    LAKE    DISTRICT.  39 

sawed  square  sets  at  mill,  $2.15;  lagging,  15  at  7  cents,  $1.05; 
cordwood  averages  from  $2.50  to  $3  per  cord. 

This  district  connects  by  several  good  roads  with  railroads. 
The  southeastern  and  central  parts,  by  three  roads  to  Calistoga — 
one  from  Oathill,  the  toll  road  from  Middletown,  and  the  toll 
road  from  the  Great  Western  mine;  distances,  from  12  to  20 
miles.  The  northwestern  part  connects  with  Calistoga  and 
Healdsburg,  and  for  the  most  extreme  northwestern  portion 
also  with  Cloverdale;  distances,  from  16  to  20  miles. 

CLEAR  LAKE  DISTRICT. 

The  southern  borders  of  Clear  Lake  and  the  adjoining  terri- 
tory have  been  a  region  of  great  volcanic  activity;  a  great 
part  of  the  territory  south,  southeast,  and  east  of  Clear  Lake 
bears  evidence  of  having  at  one  time  been  covered  by  lava 
flows,  most  of  the  ridges  being  covered  with  eruptive 
flows.  [See  Report  State  Mining  Bureau  of  Cal.,  X,  page  232.] 
Whether  these  were  ejected  from  a  few  large  vents,  or  from  a 
great  number  of  disseminated  minor  vents,  has  not  yet  been 
determined.  In  close  proximity  to  Clear  Lake,  at  Mount  Ko- 
nockti  or  Uncle  Sam,  and  in  the  territory  northwest  of  Sulphur 
Bank,  such  vents  are  undoubtedly  located.  These  eruptions 
took  place  at  different  periods,  and  ejected  lavas  of  different 
compositions.  Mount  Konockti  is  formed  bj^  later  andesites, 
which  are  also  found  to  the  northeast  of  the  lower  part  of  Clear 
Lake;  but  in  the  close  neighborhood  of  Sulphur  Bank  the 
eruptives  are  principally,  but  not  exclusively,  basalts.  These 
latter  eruptions  must  have  been  recent,  the  basalt  overlying 
the  Quaternary  Cache  Lake  beds.  To  the  northeast  of  the 
lava  flows  in  this  district  is  a  very  extensive  belt  of  serpentine; 
but  the  rocks  underlying  the  lava  flows  are,  north  of  Putah 
Creek,  prominently  sandstones  and  shales.  [See  geological 
map  of  Napa,  Sonoma,  Lake,  and  Yolo  counties  quicksilver 
deposits.] 

Around  Lower  Lake  lumber  is  worth  $17  per  1000  feet 
(B.  M.);  round  timber,  6  cents  per  linear  foot;  lagging,  6  cents 
apiece. 

This  district  finds  its  railroad  outlet  through  Calistoga. 
Lower  Lake  is  33  miles  distant  from  that  town. 


40 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


1^ 


SULPHUR   CREEK 
DISTRICT. 

The  Sulphur  Creek 
district  comprises  the 
headwaters  of  Sulphur 
Creek,  on  the  line  be- 
tween Lake  and  Colusa 
counties,  east  of  Clear 
Lake.  This  region  has 
been  considerablj-  erod- 
ed, a  great  amount  of  its 
debris  covering  to  a  con- 
siderable depth  the  coun- 
try Ij'ing  to  the  west 
toward  Cache  Creek,  a 
distance  of  three  miles 
in  an  air  line.  The  ridge 
near  the  Abbott  mine, 
forming  the  watershed 
between  Cache  Creek 
and  Bear  Creek,  is  in 
places  covered  with 
wash  gravel,  some  of 
the  pebbles  being  de- 
rived from  igneous  rocks. 

Two  nearly  parallel 
belts  of  serpentine  run 
through  the  district  [see 
special  map  of  the  dis- 
trict and  Fig.  2]  with  a 
northwest  trend.  The 
western  runs  partly  on 
above-mentioned  divide; 
the  serpentine  is  very 
siliceous  in  character 
and  rather  opaline.  On 
its  eastern  contact  with 
a  belt  of  rather  soft  sand- 
stone lies  a  zone  of 
crushed  opaline.  To  the 
west  of  this  serpentine, 


SULPHUR    CREEK    DISTRICT.  41 

between  it  and  the  adjoining  shales,  is  a  zone  of  a  light  gray 
or  yellow  material,  containing  inclusions  (varying  in  size 
from  small  pebbles  to  bowlders  of  considerable  size)  of  obsid- 
ian, chalcedonite,  and  opalinized  serpentine.  The  matrix  of 
this  breccia  is  a  tufi,  or  better,  a  tuffoid  (a  tuff  altered  by 
regional  metamorphism,  according  to  Miigge).  [See  Williams, 
Litholog}',  page  290.]  The  same  material  is  found  in  the 
Elgin  mine. 

The  surface  of  this  serpentine  has  been  leached  by  acidic 
w^aters,  leaving  a  peculiar  hard,  siliceous  material  of  a  light 
bluish-gray  color,  full  of  cavities,  and  occurring  in  thin  slabs. 
Near  the  surface  the  serpentine  is  generally  not  silicified,  but 
the  ledge  matter  is  largely  a  much  crushed  opaline  rock,  more 
friable  and  less  hard  than  the  opaline  in  the  tuffoid.  This  ser- 
pentine belt  is  not  very  long  and  is  surrounded  by  shales  and 
argillaceous  sandstones.  [See  map  of  district.]  To  the  east  is 
a  wider  and  more  continuous  serpentine  belt,  at  the  western 
contact  of  w^hich  are  located  the  Wide  Awake,  Empire,  and 
Manzanita  mines. 

The  shales  contain  bitumen,  sometimes  forming  heavy  oil, 
and  sometimes  lighter  gaseous  hydrocarbons.  The  waters 
percolating  through  these  formations  are  often  charged  with 
hydrogen  sulphide.  Occasionally  they  form  hot  springs.  A 
hot  sulphur  spring  at  Blanck's  Hotel  [see  map]  was  cut  off  by 
the  Wide  Awake  shaft  when  the  latter  was  sunk  from  the  200 
to  the  300  foot  level,  at  a  distance  of  1300  feet  from  the  spring, 
and  a  depth  of  about  300  feet  below  the  spring,  and  never 
reappeared,  cold  water  now  issuing  from  the  same  spring. 
This  proves  that  this  spring  was  caused  by  hot  ascending 
waters,  following  a  gentle  slope  of  about  1300  feet  horizontal 
to  300  feet  vertical.  The  great  amount  of  mineralized  waters, 
the  siliceous  sinters  and  sulphur  deposits  formed  by  extinct 
solfataric  springs,  and  the  still  existing  hot  sulphur  springs, 
indicate  strong  irruptive  action.  As  no  igneous  rocks  appear 
at  the  surface  in  the  immediate  neighborhood,  this  may  have 
been  laccolitic.  In  the  bed  of  Sulphur  Creek  a  conglomerate 
is  constantly  forming,  the  pebbles  in  the  creek  being  cemented 
by  deposits  from  the  water,  which  is  charged  with  sulphur  and 
sulpho-salts. 

The  shales  and  sandstones  occur  unaltered  and  in  various 
stages  of  alteration.  A  belt  of  limestone  passes  through  the 
Manzanita  property,  course  southeast,  adjoining  to  the  west  a 


42  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

belt  of  conglomerate,  a  water  formation,  similar  to  that  now 
forming  in  the  bed  of  Sulphur  Creek.  About  three  fourths  of 
a  mile  farther  on,  in  the  same  direction,  but  without  any  sur- 
face connection  with  this  limestone,  is  found  a  small  body  of 
fossiliferous  limestone,  with  fossils  of  the  Cretaceous  age 
{Rhvnchonella  whitJieyi). 

In  the  Sulphur  Creek  district  the  cost  of  sawed  timber  is 
very  high,  the  nearest  sawmill  being  28  miles  distant  and  the 
roads  very  heavy;  the  mines  use  exclusively  round  timber  at 
8  cents  per  linear  foot  for  6  inches  (smallest)  diameter.  Cord- 
wood  (oak)  costs  $s  per  cord. 

KNOXVILLE  DISTRICT. 

The  Knoxville  district,  situated  at  the  junction  of  L,ake, 
Napa,  and  Yolo  counties,  was  in  former  times  the  scene  of 
much  activity.  A  number  of  the  mines  then  in  operation  — 
Reed,  Andalusia,  Royal,  and  Grizzly— are  closed  down  and 
abandoned,  and  the  newer  prospects — Harrison,  New  Eng- 
land, Red  Elephant,  etc. — have  as  yet  disclosed  nothing  im- 
portant. 

The  two  mines  at  present  in  operation  (the  Boston  and  the 
Manhattan)  offer,  however,  many  points  of  interest.  These 
mines  are  in  proximity  to  a  basaltic  body ;  the  Manhattan  is 
in  contact  therewith,  and  the  Boston  is  in  very  close  proximity 
and  practically  in  line  with  the  direction  of  the  main  fissure 
through  which  the  basalt  was  ejected.  This  basalt  is  the  only 
eruptive  body  coming  to  the  surface  in  the  district,  and  lies 
on  the  contact  between  the  large  belt  of  serpentine  which  runs 
in  a  southeasterly  direction  from  Cache  Creek  and  the  unal- 
tered Neocomian  to  the  northeast  thereof.  This  serpentine  belt, 
which  reaches  into  Napa  County  and  is  several  miles  wide,  con- 
tains, as  far  as  yet  ascertained,  only  sporadic  signs  of  cinnabar 
ore,  and  it  is  very  doubtful  if  any  workable  deposits  will  ever 
be  found  therein. 

There  is  no  timber  in  the  vicinity  of  Knoxville.  It  has  to 
be  hauled  from  Lower  Lake,  18  miles.  Round  timber,  8  inches 
(smallest)  diameter,  costs  10  cents  per  linear  foot.  Cordwood, 
oak,  $5;  pine,  etc.,  $3.50  per  cord.  Oak  is  so  much  superior  to 
pine  in  the  furnace  that  at  $5  per  cord  it  is  not  more  expensive 
than  the  latter  at  $3.50  per  cord. 

This  district  connects  with  the  railroad  at  Rumsey,  a  dis- 
tance of  15  miles;  generally  supplies  are  hauled  from  Napa, 
40  miles  distant. 


QUICKSILVER    MINES   IN    THE    COUNTIES 
OF    CALIFORNIA. 


COLUSA   COUNTY. 

Central  Mine. — Sulphur  Creek  District.  Empire  Consoli- 
dated Quicksilver  Company,  owner;  R.  A.  Boggess,  general 
manager,  Sulphur  Creek,  Colusa  Count}'.  Consists  of  the 
Central,  Dewe}^  and  Little  Giant  claims,  in  Sec.  29,  T.  14  N., 
R.  5  W.  [See  Report  State  Mining  Bureau  of  Cal.,  XI,  page  185; 
XII,  page  359.]  This  mine  covers  a  small  triangular  territory 
on  the  left  bank  of  Sulphur  Creek,  and  is  traversed  bj^  a  ledge 
with  a  northwestern  strike,  on  the  contact  of  a  decomposed 
rock,  probably  serpentine,  and  shales  in  which  some  ore  was 
found  near  the  surface. 

Elgin  Mine. — Sulphur  Creek  District.  Elgin  Quicksilver 
Mines,  owner;  C.  F.  Humphrey,  president.  No.  137  Mont- 
gomer}'  street,  room  15,  San  Francisco.  In  Sec.  13,  T.  14  N., 
R.  6  W.  [See  Report  State  Mining  Bureau  of  Cal.,  XI,  page 
182;  XII,  page  359.]  The  mine  is  situated  near  the  head  of 
Sulphur  Creek,  and  is  at  present  idle.  The  main  tunnel  is 
caved  in  120  feet  from  the  entrance.  The  ledge  matter  is  a 
tuffoid  very  highl}'  impregnated  by  sulphur,  and  decomposed. 
The  entire  territory  covered  by  this  mine  is  so  highly  impreg- 
nated by  sulphur  that  attempts  have  been  made  to  distill  sul- 
phur from  the  rock.  Another  tunnel,  60  feet  below  the  main 
tunnel,  is  also  caved  in;  hot  water,  very  high  in  sulphur,  is 
flowing  out  of  it.  A  number  of  shallow  openings  on  the  line 
of  the  croppings  show  on  the  dump  some  cinnabar-bearing 
material.  The  excessive  heat  in  the  mine  interfered  to  a  certain 
extent  with  its  operation.  Some  quicksilver  was,  however, 
made  in  a  lo-pipe  retort  furnace  belonging  to  the  property. 

Empire  Mine. — Sulphur  Creek  District.  Empire  Consolidated 
Quicksilver  Company,  owner;  R.  A.  Boggess,  general  manager, 
vSulphur  Creek,  Colusa  County.  This  consists  of  four  claims — 
Empire,  Hidden  Treasure,  Mercury  King,  and  Mercury  Queen. 


44  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

In  Sec.  28,  T.  14  N.,  R.  5  W.  [See  Report  State  Mining  Bureau 
of  Cal.,  XI,  page  186.]  There  are  several  drifts  and  open  cuts 
on  the  propert)',  but  none  showing  any  ore  body  of  conse- 
quence. The  company  is  now  sinking  a  vertical  shaft  in  the 
northwestern  part  of  the  propert}'. 

Manzanita  Mine. — Sulphur  Creek  District.  Manzanita  Gold 
Mining  Company,  owner;  G.  V.  Northey,  lessee.  Sulphur  Creek, 
Colusa  County.  In  Sec.  29,  T.  14  N.,  R.  5  \V.  [See  Mon. 
XIII,  U.  S.  G.  S.,  page  367;  Report  State  Mining  Bureau  of 
Cal.,  X,  page  160;  XI,  page  184;  XIII,  page  126.]  This  mine 
was  opened  about  1865,  but  was  worked  onl}'  for  gold  until 
1892,  when  it  was  also  worked  for  quicksilver,  and  up  to  lately 
mostl}^  by  surface  work  and  short  drifts.  The  rocks  of  a  large 
part  of  the  territor}'  covered  by  this  mine  consist  of  sandstones 
and  shales,  intersected  by  narrow  quartz  seams,  containing 
gold,  sometimes  associated  with  cinnabar;  these  seams  had 
occasionally  very  rich  spots,  but  as  they  are  very  thin,  and 
separated  by  wide  blocks  of  barren  country  rock,  their  work- 
ing was  not  very  profitable  and  could  onh-  be  carried  on  at  all 
by  surface  cuts,  etc.  The  deposits  occur  on  both  sides  of 
Sulphur  Creek ;  on  the  west  side  of  the  creek  the  formation  is 
sandstone;  on  the  opposite  side  of  the  creek  it  is  more  shaly. 
In  both  places,  extensive  old  works  can  be  seen  at  and  near 
the  surface.  Bej-ond  this  surface  zone  the  shaly  country  rock 
east  of  the  creek  is  barren.  Farther  down  along  the  creek,  on 
the  same  side  close  above  the  mill,  the  sidehill  consists  of  a 
white  rock,  evidently  the  country  rock  leached  by  waters 
coming  from  sulphur  springs  formerly  situated  higher  up  the 
hillside.  This  leached  material  carries  both  gold  and  quick- 
silver. The  leaching  process  is,  however,  only  superficial,  and 
the  mineralization  must  be  due  to  the  action  of  the  same 
waters,  for  the  countr}^  rock  past  this  zone  of  leaching  has 
proven  to  be  barren.  At  present  the  gold  deposits  are  not 
worked.  The  work  is  confined  to  the  quicksilver  deposit  on 
the  northeastern  part  of  the  Manzanita  claim,  where  the  ore 
carries  only  quicksilver  and  no  gold.  The  shaft  is  on  the  top 
of  a  knoll,  at  an  elevation  of  475  feet  above  Sulphur  Creek. 
A  ledge  of  conglomerate,  from  20  to  30  feet  wnde,  of  the  same 
nature  as  the  conglomerate  now  forming  in  the  bed  of  vSulphur 
Creek,  crosses  the  hill  in  a  northwesterly  direction,  and  on  the 
southeastern  sidehill  siliceous  sinters  are  found. 


COLUSA    COUNTY.  45 

In  the  mine  near  the  shaft  a  whitish  friable  material  (leached 
sandstone)  carries  sensible  amounts  of  cinnabar.  The  ledge  is 
very  winding  in  both  strike  and  dip;  the  accompanying  gouge 
is  also  very  irregular.  The  hanging-wall  shale  is  in  places 
altered  to  a  whitish  material  ver}^  similar  to  that  above  men- 
tioned. The  ledge  material,  especially  in  the  lower  150-foot 
level,  is  principally  chalcedonite.  In  places  conglomerate  is 
found  on  the  foot  wall  of  the  ledge,  but  it  is  doubtful  if  the 
real  foot  wall  has  been  reached.  This  deposit  shows  plainly 
that  it  is  the  result  of  deposition  out  of  solfataric  waters,  as 
well  in  the  ore  body  as  by  their  action  on  the  adjacent  rocks. 
To  the  west  of  the  deposit  lies  a  belt  of  limestone,  adjoining  at 
the  west  to  a  belt  of  conglomerate. 

In  the  old  workings  are  found  some  phenomena,  which  have 
a  bearing  on  the  genesis  of  cinnabar  ores.  In  an  abandoned 
tunnel,  on  walls  which  originally  showed  no  signs  of  cinnabar, 
a  great  amount  of  sulpho-salts  is  forming,  accompanied  in 
places  with  cinnabar,  generally  as  a  coating  of  the  wall,  but 
occasionally  successive  layers  of  silica  have  been  found  inclos- 
ing a  thin  seam  of  cinnabar.  As  proof  that  this  cinnabar  for- 
mation is  going  on  at  present,  pieces  of  barren  country  rock 
lying  on  the  floor  have  been  coated  with  cinnabar  on  the  face 
touching  the  wall  similarly  coated,  while  no  signs  of  cinnabar 
can  be  found  on  any  other  face,  nor  on  any  similar  rock  not  in 
contact  with  the  wall.  The  cinnabar  must  hence  have  been 
derived  by  exudation  out  of  the  wall  rock.  The  tunnel  is 
perfectly  dry,  and  the  only  water  found  therein  on  the  floor  is 
some  seepage  from  the  surface  after  heavy  rains,  this  cinnabar 
formation  taking  place  at  a  very  shallow  depth. 

The  reduction  works  of  the  Manzanita  mine  are  specially 
interesting,  as  the  quicksilver  ores  are  successfully  concen- 
trated, and  the  concentrates  treated  in  retorts  at  a  sensibly 
reduced  cost  per  ton  of  ore  treated.    [See  chapter  on  Metallurgy.] 

Wide  Awake  Mine  (Buckeye).— Sulphur  Creek  District.  W.  H. 
Martin,  Crocker  Building,  San  Francisco,  and  A.  A.  Gibson, 
Sulphur  Creek,  Colusa  Count5^  owners.  In  Sees.  28  and  29, 
T.  14  N.,  R.  5  W.  [See  Report  State  Mining  Bureau  of  Cal., 
XI,  page  187;  XIII,  page  594.]  The  main  workings  consist 
of  a  vertical  shaft  500  feet  deep,  with  some  short  drifts.  This 
shaft  is  now  filled  with  water  above  the  first  level.     Near  the 


46  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

northwest  end  of  the  claim  is  an  open  cut  with  some  short 
tunnels  and  winzes.  Rich  ore  pockets  have  been  worked  out, 
but  do  not  seem  to  continue  in  any  direction.  The  mine  is 
equipped  with  a  very  fine  reduction  plant  consisting  of  a  24-ton 
fine-ore  furnace,  which  has,  however,  been  scarcely  used. 

LAKE  COUNTY. 

Abbott  Mine. — Sulphur  Creek  District.  Empire  Consolidated 
Quicksilver  Mining  Company,  owner;  R.  A.  Boggess,  general 
manager.  Sulphur  Creek,  Colusa  County.  Includes  the  Abbott 
and  Disturnell  mines.  In  Sees.  30,  31,  and  32,  T.  14  N., 
R.  5  W.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  368;  Report  State 
Mining  Bureau  of  Cal.,  XI,  page  239;  XII,  page  360;  XIII, 
page  595.]  This  mine  was  discovered  in  1862.  In  1870  a 
furnace  of  a  daily  capacity  of  10  tons  was  erected  and  operated 
until  1879.  The  mine  was  idle  from  1879  to  1889.  In  1899 
the  property   was  equipped  with   a    40-ton  Hlittner  &  Scott 

W.  ,  8 


Fig.  3.     Abbott  Mine,  Lake  County— Section  over  the  serpentine. 

furnace.  The  total  production  has  been  about  30,000  flasks. 
Including  the  old  works  there  are  15,000  linear  feet  of  shafts 
and  drifts.  The  deepest  working  is  350  feet  below  collar  of 
the  Boggess  shaft.  This  mine  lies  on  the  southwestern  con- 
tact of  a  serpentine  belt,  strike  northwest,  with  a  shale  country 
rock,  occasionally  sandstone.  The  serpentine  varies  in  width 
from  a  few  hundred  feet  to  a  quarter  of  a  mile,  and  is  about* 
2>^  miles  long.  To  the  northeast  is  a  belt  of  sandstone,  rather 
narrow  in  the  southern  portion,  but  widening  rapidly  going 
northward.  [See  map  of  Sulphur  Creek  District.]  The  ser- 
pentine is  interstratified  with  beds  of  shales  and  sandstone  [see 
Fig-  3 — a  crosscut  on  the  road  from  the  Abbott  mine  to 
Sulphur  Creek] ;  the  same  alternations  are  found  underground. 
For  instance,  near  the  intersection  of  the  Reardon  tunnel 
and  the  first  level  [see  Fig.  4];  near  the  Boggess  shaft  in  the 
first  level,  where  two  serpentine  ledges  have  been  exposed  [see 
Fig.  5 J;  in  drift  II  of  the  old  works  [see  Fig.  5],  etc.     To  the 


LAKE    COUNTY. 


47 


west  of  the  serpentine  lies  the  body  of  brecciated  tuffoid — 
more  especially  described  in  the  general  description  of  the 
Sulphur  Creek  district.  The  map  of  the  mine  workings  indi- 
cates that  they  follow  generally  the  line  of  contact  of  the 
tuffoid,  wnth  the  shales  lying  west  thereof.  At  some  places, 
as  at  the  intersection  of  the  Reardon  tunnel  and  the  first  level 
[see  above],  serpentine  is  found  west  of  this  contact.  There 
is  no  doubt  that  the  same  alternations  of  serpentine  and  shales 
take  place  east  of  the  territory  at  present  opened.  The  exten- 
sive slides  found  at  the  surface  in  Disturnell  Caiion,  and  the 
reverse  dip  found,  the  rocks  having  been  tilted  over  by  the 
pressure  of  the  sliding  material,  lead  to  the  expectation  of 
irregularities  in  the  un- 
derground  formations. 
Near  the  Boggess  shaft 
this  is  ver}'  clearly  illus- 
trated. The  shales  west 
of  the  serpentine  contain 
some  hydrocarbons.  In 
places  petroleum  is 
found;  in  others,  gases 
of  light  inflammable  hy- 
drocarbons emanate  from 
the  rock,  or  bubble  up 
through  the  water.  A 
few  feet  southeast  of  the 
end  of  the  Reardon  tun- 
nel in  the  first  level  is  a  mmeral  spring  containing  carbonate 
of  magnesium,  calcium,  sodium,  and  lithium,  and  also  some 
sulphur  compounds.  The  cinnabar  ore  forms  in  these  bands 
of  serpentine,  more  especially  in  close  proximity  to  the  tuffoid; 
exceptionally  the  ore  is  found  in  the  shale.  The  gangue  is 
generally  strongly  crushed  opaline.  Metacinnabarite  occurs 
occasionally,  but  no  native  mercury  has  as  yet  been  found. 
The  cinnabar  is  disseminated  through  the  crushed  opaline, 
partly  as  face  metal,  but  also  in  seams  and  pockets.  The  ore 
zones  contain  a  great  amount  of  iron  sulphides,  in  varying 
quantities,  rendering  it  very  difficult  to  regulate  the  temper- 
ature in  the  furnace.  Very  little  gouge  is  found  between  the 
ore  bodies  and  the  walls.  The  ground  in  the  ore  zones  and 
in  the  shales  is  often  swelling,  but  the  tuffoid  stands  very  well. 


Fig.  4.  Abbott  Mine— Plan  near  inter- 
section of  Reardou  tuuuel  and  first 
level . 


48  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

In  the  lower  250-foot  level  at  the  Boggess  shaft,  an  ore  bod^'- 
was  found,  averaging  30  feet  in  width  and  1 50  feet  long,  which 
pinched  out  in  the  intermediary  level  50  feet  above,  reappear- 
ing, however,  in  the  upper  150-foot  level.  In  the  intermediary 
level,  140  feet  from  the  shaft,  50  feet  of  fair  ore  was  found. 
In  the  first  (upper)  level,  two  ore  bodies  were  followed,  and  a 
crosscut  is  started  at  the  southeast  end  of  the  lower  level  to 
cut  the  more  easterly  ore  body.      [See  Fig.  5.] 

The  first  level  has  been  driven  over  1500  feet,  largely  in  the 
hanging-wall  shales,  to  find  the  ore  bodies  existing  in  the 
northwestern  part  of  the  Lightner  level,  about  65  feet  above 
the  first  level.  Two  ore  bodies,  marked  A  and  B,  were  found 
and  stoped.  Near  A,  a  shaft  is  sunk  from  the  first  level  to  tap 
this  ore  body  below,  to  a  depth  of  130  feet.  The  ore  bodies 
opened  farther  east  by  the  lyightner  level  have  not  as  yet  been 
reached  by  the  first  level.  The  territory  between  a  point 
250  feet  west  of  the  Boggess  shaft  and  A,  a  distance  of  about 
1000  feet  in  an  air  line,  below  the  level  of  the  collar  of  the 
shaft,  is  practically  unexplored  ground;  old  surface  workings 
indicate  that  such  exploration  might  lead  to  a  discovery  of 
workable  ore  bodies. 

The  mine  is  equipped  with  a  48-ton  Scott  furnace.  The  ore 
is  dried  on  a  special  drier  located  between  the  crusher  and  the 
furnace,  having  its  own  heating  furnace. 

The  Anderson  Prospects. — Mayacmas  District.  In  Sees.  25  and 
35,  T.  II  N.,  R.  8  W.  Owners,  the  Anderson  family,  Anderson 
Springs,  Lake  County.  On  the  ridge  between  Bear  Creek  and 
the  south  fork  of  the  Putah,  in  section  35,  about  half  a  mile 
south  of  Anderson  Springs,  a  seam  of  good  cinnabar  ore  has 
been  to  some  extent  opened  up  in  a  very  much  decomposed 
sandstone.  About  one  quarter  of  a  mile  southeast  of  Ander- 
son Springs,  in  Sec.  25,  T.  1 1  N.,  R.  8  W.,  at  an  elevation  of  300 
feet  above  the  springs,  the  formation  is  strongly  saturated  with 
sulphur,  which  has  thoroughly  decomposed  the  country  rock, 
wherefrom  its  local  name  of  Sulphur  Bank.  The  upper  part 
consists  of  thin,  flat  beds  of  quartzose  rocks  interbedded  with 
clay  seams  (possibly  a  series  of  chert  beds,  like  the  ledge  mat- 
ter of  the  Great  Western,  but  too  decomposed  to  be  absolutely 
classified).  The  quartzose  rock  carries  on  its  fracture  faces 
cinnabar;  when  broken  it  proves  to  contain  a  great  amount  of 


LAKE    COUNTY.  49 

iron  sulphides.  Its  structure  would  indicate  that  the  two 
metallic  sulphides  were  not  deposited  simultaneously.  [See 
1 6th  Ann.  Rep.  U.  S.  G.  S.,  Part  II,  page  448,  3d  line  from  top.] 
The  softer  decomposed  clayey  material  does  not  contain  any 
cinnabar;  this  material  was  probably  decomposed  by  the  action 
of  the  waters  highlj^  charged  with  sulphur  on  the  less  compact 
seams.  This  sulphur  deposition  must  be  of  a  different  period 
from  that  of  the  sulphides.  Below  these  beds  lies  thoroughly 
decomposed  sandstone,  having  a  nearly  vertical  bedding, 
wherein  lies  a  2-foot  seam  of  quartzose  material,  similar  to  the 
more  compact  part  of  above  described  beds,  standing  parallel 
to  the  dip  of  the  inclosing  sandstone  and  carrjdng  some  cinna- 
bar. All  the  water  at  this  Sulphur  Bank  is  cold,  while  a 
quarter  of  a  mile  distant  are  the  hot  sulphur  springs  and  blow- 
holes, from  which  hot  sulphur  vapors  emanate,  without  anj' 
formation  of  cinnabar  ore. 

Baker  Mine.— Clear  I^ake  District.  S.  T.  Palstine,  Lower 
Lake,  Lake  County,  owner.  In  Sec.  16,  T.  12  N.,  R.  6  W. 
[See  Mon.  XIII,  U.  S.  G.  S.,  page  368;  Report  State  Mining 
Bureau  of  Cal.,  X,  page  67;  XII,  page  360;  XIII,  page  595.] 
Consists  of  the  Baker  and  Trade  claims.  This  mine  lies  on 
a  belt  of  serpentine  cutting  through  the  sandstones  and  prob- 
ably abutting  against  the  basalt  bounding  Soda  Creek  Valley 
to  the  west.  The  lower  tunnel  crosscuts  the  formation,  and  as 
the  slope  of  the  hill  is  very  fiat,  it  gains  very  little  depth.  The 
first  140  feet  are  in  ver}'  tough  black  clay,  then  20  feet  of  serpen- 
tine, when  the  ledge  is  reached,  along  which  they  have  drifted 
for  250  feet.  In  a  stope  20  feet  high,  the  seams  have  been 
partially  filled  with  quartz,  upon  which  have  been  deposited  a 
coating  of  iron  pyrites,  which  are  coated  with  metacinnabarite. 
Cinnabar  also  forms  in  the  serpentine  associated  with  iron 
pyrites.  Farther  on  in  the  drift  it  forms  in  the  fissures  and  seams 
of  serpentine,  and  is  to  a  less  degree  associated  with  iron;  yet 
throughout  the  entire  mine  iron  occurs  verj-  prominently  in 
association  with  cinnabar  and  metacinnabar.  About  800  feet 
north  of  this  tunnel  is  a  tunnel,  course  about  north,  75  feet 
long.  The  ledge  matter  is  an  opaline  silica,  carrying  cinnabar 
and  iron  pyrites,  entirely  different  from  that  in  the  first  named 
tunnel  where  the  gangue  is  tjuartz.  A  little  southeast  of  this 
tunnel  and  about  25  feet  lower,  another  tunnel  runs  about  east 

4— OR 


50 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


at  right  angles  to  the  preceding,  crosscutting  the  formation. 
This  tunnel  is  caved  in,  but  judging  from  the  material  on  the 
dump  it  has  reached  the  ledge.  About  300  feet  northwest  of 
this  tunnel  and  30  feet  lower,  a  third  tunnel  has  been  run 
S.  54°  E.,  for  235  feet;  then  S.  24°  E.,  26^/^  feet  to  the  opaline 
ledge,  where  it  is  connected  by  a  winze  with  the  end  of  the 
former  tunnel;  the  ledge  is  about  25  feet  wide.  To  the  north- 
west of  these  works  a  strong  mineral  spring  is  forming  quite 
a  large  mound  on  the  hillside.  The  mine  is  equipped  with  a 
lo-pipe  retort  furnace. 

The  Big  Injun  Group* — Mayacmas  District.     In  Sec.  2,  T.  10  N., 
R.  8   W.,  and  Sec.  35,  T.  11  N.,  R.   8  W.— on  both  sides  of 

y 


f^  t'  £>    ay'yn  C  ly  ^2 


J?^ 


^«/A 


r^r 


1?,^yrfy.,. 


fro<ffi/'rt.qt 


Fig.  6.     Big  Injun  Group,  Lake  County. 


Bear  Creek.  Consists  of  two  claims,  the  Big  Injun  and  the 
Digger  Injun.  The  property  is  located  on  a  very  irregular  and 
disconnected  line  of  croppings,  showing  only  over  a  short  dis- 
tance south  of  Bear  Creek,  and  apparenth"  faulted  or  displaced 
in  the  gulch  through  which  that  creek  flows.  [See  Fig.  6.] 
The  country  rock  is  serpentine  and  sandstone,  very  much  mixed. 
On  the  south  side  of  the  creek  only  surface  indications  of  cin- 
nabar are  found.  On  the  north  side,  cinnabar  ore  has  been 
found  in  man^^  shallow  openings;  in  one,  3  inches  of  good 
cinnabar  ore  is  disclosed  in  a  quartz  seam  in  the  opaline  rock 
over  a  length  of  15  feet,  but  nothing  assuring  permanency  in 
depth  has  yet  been  developed. 

[Since  writing  the  above,  these  claims  have  been  segregated. 
The  Big  Injun  belongs  to  the  New  Phoenix  Mining  Company, 


LAKE    COUNTY. 


51 


and    the    Digger    Injun    to   the    Congress    Mining    Company. 
Theo.  A.  Bell,  president,  Behlow  Building,  Xapa.] 

Chicago  Mine  (Ural). — Mayacmas  District.  In  Sec.  i,  T.  lo  N., 
R.  8  W.  About  half  a  mile  west  of  the  Wall  Street  mine,  and 
nearly  at  the  head  of  Dry  Creek.  [See  Report  State  Mining 
Bureau  of  Cal.,  XIII,  page  595.]  Owners,  U.  G.  Schreves,  of 
Mirabel,  Lake  Count}',  and  others.  In  a  large  open  cut,  from 
which   former   owners   have  taken  125  flasks  of   quicksilver. 


PHuTu  Xu.   1.     CHICAGO  PLANT. 

with  a  short  drift  and  a  shaft  12  feet  deep,  is  a  ledge  of  hard 
opaline  rock,  with  only  a  little  cinnabar  in  the  cross  fissures, 
having  a  strike  X.  23"  W.,  and  a  dip  to  the  southwest  about 
60°.  This  is  overlaid  by  a  seam  carrj-ing  cinnabar  and  also 
some  native  mercury,  in  turn  overlaid  by  one  foot  of  softer 
ledge  matter  carr^'ing  fair  values  in  cinnabar  and  native 
mercur}-;  then  comes  about  4  feet  of  more  or  less  decomposed 
serpentine,  and  then  the  serpentine  hanging  wall.  The  foot 
wall  is  probably  serpentine,  but  has  not  been  uncovered.  [See 
Fig.  7.]     A  lower  tunnel,  65  feet  below  the  open  cut,  80  feet 


52 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


long,  has  a  long  stope  40  feet  high  to  the  surface  and  at  the 
breast  a  winze  16  feet  deep;  both  on  the  same  seam,  which 
here  has  a  metal- carrying  zone  3  feet  wide,  showing  no  native 
mercury.  [See  Fig.  8.]  A  very  crooked  crosscut  tunnel,  60 
feet  lower  down  the  hillside,  has  not  reached  the  ledge. 


3  yy.  I 

Fig.  7.     Section  of  Chicago  Mine. 


Fig.  8.     Section  of  Chicagfo  Mine. 


Great  Western  Mine* — In  Sees.  16,  21,  and  22,  T.  10  N.,  R.  7  W. 
Owner,  The  Great  Western  Quicksilver  Mining  Company,  E.  W. 
Newhall,  president,  Nos.  309-311  Sansome  street,  San  Fran- 
cisco; John  Andrews,  superintendent,  Quicksilver,  Lake  Count}'. 
[See  Mon.  XIII,  U.  S.  G.  S.,  page  35S;  Report  State  Mining 
Bureauof  Cal.,XI,page64;  XII,page36i;  XIII,page595.]  The 
Great  Western  mine  was  opened  in  1873,  and  has  been  a  con- 
stant producer  since  1 874.  The  total  production  is  about  90,000 
flasks.  There  are  about  18,000  feet  of  drifts  and  11 50  feet  of 
shafts  in  the  mine;  the  greatest  depth  of  the  workings  is  750 
feet.  This  mine  is  situated  about  two  miles  northwest  of  the 
Mirabel  and  Bullion  mines.  The  serpentine  belt  in  the  inter- 
vening space  is  very  wide  and  prominent,  but  as  yet  no  work- 
able cinnabar  deposits  have  been  discovered  therein,  nor  on  its 
contact  with  the  eruptives  forming  the  main  ridge  northwest 
of  INIount  St.  Helena.  Whether  the  latter  are  onl)-  lava  flows 
from  the  igneous  masses  forming  IMount  St.  Helena,  or  form 
part  of  these  masses,  has  not  j'et  been  determined.  At  and 
near  the  Great  Western  mine  the  serpentine  belt  is  much  nar- 
rower, being  confined  between  a  wide  sandstone  formation  to 
the  east  and  the  above-mentioned  bod}'  of  eruptive  rocks. 

The  present  workings  are  southeast  of  those  in  operation 


54  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

when  Dr.  Becker  examined  the  mine  [see  Mon.  XIII,  U.  S.  G.  S.] , 
which  explains  some  differences  between  the  two  descriptions. 
The  general  strike  of  the  ore  body  is  northwest,  with  a  south- 
western dip  of  about  70°.  The  foot  wall  is  a  very  hard  sedi- 
mentary rock  altered  by  silicification,  locally  called  greenstone. 
The  hanging  wall,  at  least  at  the  surface,  is  serpentine.  The 
ledge  matter  is  formed  by  a  series  of  thin  beds  of  chert,  having 

their      bedding     planes 

^^^'\^k.^^~-~)>-/ ^  parallel  to  the  strike  of 

the  ledge  and  interstrat- 
ified  with  clay  seams. 
This  chert  is  locally 
called  quartzite.  The 
dip  of  the  serpentine  is 
flatter  than  that  of  the 
ledge  matter,  and  the 
\-  intervening,      widening 


S".  vV  space  is  filled  with  black 

Fig.  9.     Cross-section  of  Great  Western  Mine.  Sita.  [OCe       -Tig.      9-J 

The  main  working  shaft 
is  sunk  vertically  in  the  foot-wall  greenstone,  and  is  on  the 
600-foot  level,  340  feet  northeast  of  the  ledge. 

The  ore  forms  in  the  chert  ledge,  in  a  very  irregular  manner; 
generally  in  the  seams,  and  as  face  metal  in  the  fractures  of 
the  chert,  but  in  the  richer  parts  of  the  ledge  disseminated 
through  the  chert  itself,  associated  with  iron  pyrites.  The  ore 
bodies  occur  very  irregularly  in  this  chert  zone,  and  the  only 
available  indication  for  the  occurrence  of  pay  ore  is  the  fact 
that  the  mineralization  is  in  general  the  strongest  in  those 
parts  where  the  chert  beds  have  been  more  or  less  crushed. 
The  ore  forms  very  seldom  in  the  serpentine,  but  some  bunches 
of  very  hard  and  rich  ore  have  been  found  in  the  serpentine, 
without,  however,  any  continuity.  The  black  gouge  is  less 
clayey  and  less  foliated  than  generally  in  these  ore  deposits. 
The  increase  in  width  of  the  hanging-wall  gouge  in  depth  is  the 
reason  that  no  serpentine  is  uncovered  in  the  lower  workings; 
and  as  no  crosscuts  have  been  run  through  the  gouge  to  the 
hanging-wall  country  in  the  lower  levels,  the  persistency  of  the 
serpentine  in  depth  is  not  established.  On  the  600-foot  level  a 
body  of  good  grade  ore,  over  200  feet  long  and  50  feet  wide,  has 
been  opened  up,  which  continues  upward  to  about    70   feet 


LAKE    COUNTY.  55 

above  the  500-foot  level.  A  "horse"  has  come  in,  and  throws 
the  ore  body  somewhat  out  of  its  course,  so  that  it  has  not  yet 
been  reached  in  the  700-foot  level.  A  drainage  tunnel,  2200 
feet  long,  runs  through  the  foot-wall  material,  connecting  with 
the  500-foot  level.  This  tunnel  crosses  some  very  narrow  belts 
of  serpentine,  but  passes  mainly  through  sandstone,  until  at 
about  1 200  feet  from  the  entrance  it  reaches  a  belt,  500  feet 
wide,  of  decomposed,  impervious  shales,  next  to  which  lies  the 
foot-wall  greenstone,  about  450  feet  wide,  which  is  more  or 
less  decomposed  near  the  ledge,  but  at  a  distance  of  a  few  feet 
therefrom  becomes  very  hard  and  compact,  and  carries  con- 
siderable iron  pyrites.  [See  Fig.  10.]  This  greenstone  has 
certainly  not  the  appearance  of  being  the  source  of  the  cin- 
nabar, as  the  sandstone  at  Oathill,  ^tna,  etc.      The  formation 


Fig.  10.     Section  over  the  Great  Western  Mine. 

shows  great  displacement  and  distortion  and  great  bowlders 
of  the  neighboring  series  are  found  imbedded  in  the  rock, 
indicating  strong  dynamic  action.  On  the  strike  of  the  ledge 
ore  is  at  present  only  extracted  from  one  ore  shoot,  but  the 
company  is  doing  considerable  underground  prospecting  work 
to  find  reserves  for  future  development.  The  ore  is  treated  in 
a  Litchfield  furnace  of  50  tons  capacity. 

Helen  Mine  (American).— May acmas  District.  In  Sec.  i, 
T.  10  N.,  R.  8  W.  About  half  a  mile  south  of  the  Wall 
Street  mine,  in  the  upper  part  of  Dry  Creek  basin.  Owner, 
Andrew  Rocca,  Middletown,  Lake  County.  [See  Mon.  XIII, 
U.  S.  G.  S.,  page  375;  Report  State  Mining  Bureau  of  Cal.,  XII, 
page  362.]  This  mine  is  at  present  the  only  one  in  the  Dry 
Creek  basin  which  produces  quicksilver.  It  lies  very  close  to 
the  tufas  of  Pine  Mountain.  The  vein  matter  is  a  mixture  of 
opaline  rock  and  serpentine,  containing  numerous  inclusions  of  a 
black  flinty  rock.  The  strike  of  the  ledge  is  about  due  east  and 
west:  its  dip  underground  southerly,  rather  fiat,  30°  to  40°. 


56 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


The  ledge  lies  at  the  contact  of  the  sandstone  and  serpentine 
[see  Fig.  ii],  and  can  be  readily  traced  on  the  surf  ace  for  quite 
a  distance.  In  places  the  ledge  crops  out  boldly  above  the  sand- 
stone, showing  occasionally  the  cla}^  gouge,  weathered  to  a 
white  color,  indicating  that  the  black  color  is  principalh-  due 
to  iron,  probably  in  the  form  of  mono-sulphide.  At  the  north 
end  of  the  claim,  eruptive  rock  (probably  basaltic)  shows  on 
the  surface  near  the  hanging  w^all,  but  as  no  eruptive  rock  has 
as  yet  been  found  in  the  underground  workings,  this  may  be  a 
flow  from  Pine  Mountain.  The  cinnabar  is  accompanied  by  a 
great  amount  of  iron  sulphide;  it  forms  mostly  in  the  fissures 
and  cracks  of  the  vein  filling,  sometimes  forming  seams  of 
solid  cinnabar  an  inch  or  more  wide.     The  strike  of  these  cin- 


FiG.  II.    Cross-section  of  Helen  Mine,  Lake  County. 

nabar  seams  is  parallel  to  the  general  strike  of  the  ledge.  In 
the  ore  shoot  the  vein  filling  is  less  compact  on  the  foot  wall, 
and  the  cinnabar  seams  are  in  places  several  inches  wide,  the 
cinnabar  besides  permeating  the  entire  rock.  A  gouge  seam 
separates  this  richer  ore  from  the  overlying  relatively  poorer 
ore,  which  seems  to  indicate  a  movement  during  the  period  of 
metal  deposition,  the  gouge  seam  localizing  the  latter  deposition. 
[See  Fig.  ii.]  The  ore  shoot,  in  fact,  as  far  as  at  present 
opened,  shows  cinnabar  in  nearly  every  fracture  plane.  The 
ledge  is  reached  by  a  crosscut  tunnel,  running  nearly  south, 
through  the  foot-wall  serpentine  and  driven  to  the  hanging- 
wall  sandstone,  which  it  reaches  at  a  distance  of  347  feet,  with 
140  feet  of  backs.  The  ledge  as  cut  by  the  tunnel  is  120  feet 
wide,  of  which  100  feet  is  ore-bearing.  The  ore  shoot  has  been 
developed  along  the  strike  over  a  length  of  80  feet.  At  the 
breast  of  the  tunnel  a  vertical  shaft  is  in  process  of  sinking, 
which  has  cut  through  the  vein  and  is  in  the  foot-wall  ser- 
pentine.    A  lower  tunnel,  running  about  parallel  to  the  one 


LAKE   COUNTY.  0/ 

above  described,  1300  feet  long,  has  not  yet   reached  the  vein, 
due  to  its  flat  southerly  dip. 

A  lo-retort  plant,  with  a  daily  capacity  of  1500  pounds  of 
ore,  is  in  operation  to  test  the  value  of  the  ore  mined.  The 
great  amount  of  iron  sulphides  carried  by  the  ore  necessitates 
a  very  slow  treatment,  only  one  charge  being  treated  per 
twenty-four  hours. 

Jewess  Mine. — Majacmas  District.  In  Sees,  i  and  12,  T.  10  X., 
R.  8  W.;  Sees.  6  and  7,  T.  10  N.,  R.  7  W.  Some  work  has 
been  done  on  croppings  of  the  same  character  and  probabh' 
belonging  to  the  same  body  as  those  on  the  Wall  Street  mine, 
on  the  opposite  or  southwest  side  of  Dry  Creek.  These  crop- 
pings appear  to  be  barren.  A  tunnel,  run  about  75  feet  lower 
down  the  sidehill,  has  caved  in,  but  the  dump  shows  no  sign 
of  ore.  Judging  from  common  report  no  ore  has  ever  been 
taken  out  of  this  propert}'. 

King  of  All  Consolidated  Group. — Clear  I^ake  District.  Owners, 
D.  Jones,  Xo.  137  Montgomery  street,  San  Francisco;  W.  G. 
Temper,  Lower  I^ake,  Lake  Count)^  In  Sees.  29  and  32, 
T.  12  N.,  R.  7  W.  The  group  consists  of  the  King  of  All, 
Trejon,  Cinnabar  Queen,  and  Eagle  Bird  claims.  This  mine 
is  situated  on  a  belt  of  serpentine,  having  a  general  northwest 
trend.  Bad  Cailon  Creek  runs  through  this  property  and  cuts 
through  the  serpentine  to  the  underlying  schist.  The  lower 
tunnel,  a  little  above  the  bed  of  the  creek,  is  in  serpentine. 
Its  direction  is  nearly  west.  At  about  100  feet  from  the  mouth 
a  side  drift  is  run  in  a  northwesterly  direction  on  a  spur,  with 
a  small  stope  showing  the  serpentine  walls.  The  tunnel 
passes  two  other  spurs,  and  at  150  feet  reaches  what  is  con- 
sidered the  main  ledge,  which  has  a  northwesterly  course,  with 
dip  nearly  vertical.  The  tunnel  is  run  12  feet  farther,  the 
breast  being  still  in  ledge  matter.  There  is  so  much  fire  damp 
in  this  mine  that,  as  the  air  blower  could  not  be  used,  it  was 
too  dangerous  to  break  any  ore;  hence  the  character  of  the 
ledge  matter  could  not  be  determined.  The  wall  rock  is  in 
places  strongly  decomposed,  showing  the  action  of  solfataric 
waters.  To  the  northeast  of  the  serpentine  lies  a  large  body 
of  tufas  and  volcanic  bowlders,  and  about  a  mile  north  of  the 
King  of  All  mine  is  Howard  Springs,  a  region  of  ver>-  strong 
solfataric  action,  containing  within  a  very  small  area  forty-two 


58  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

mineral  springs,  some  hot,  others  cold,  and  of  the  most  vary- 
ing chemical  composition.  It  is  claimed  that  in  the  waters  of 
one  of  the  springs,  mercurial  salts  have  been  detected.  The 
ore  composition  in  the  King  of  All  mine  has  most  probably 
some  connection  with  the  solfataric  action  at  these  springs. 
The  igneous  rocks  above  alluded  to  belong  probably  to  the 
system  of  the  Mount  Konockti  eruptives.  That  they  are  in 
some  way  connected  with  the  genesis  both  of  the  mineral 
springs  at  Howard  Springs  and  of  the  cinnabar  ore  deposits 
at  the  King  of  All  mine,  appears  very  probable. 

Lucitta  Mine.— Clear  Lake  District.  G.  W.  Pardee,  E;  G. 
Pardee,  B.  R.  Parrott,  Lower  Lake,  Lake  County,  owners.  In 
Sees.  20  and  21,  T.  13  N.,  R.  8  W.  This  property',  on  the 
southern  slope  of  Mount  Konockti,  or  Uncle  Sam,  consists  of 
four  claims:  the  Lucitta,  Lucitta  Extension  N.,  Lucitta  Exten- 
sion S.,  and  Lucitta  Extension  W.  [See  Fig.  12.]  The  work, 
however,  has  been  concentrated  in  the  southern  half  of  the 
Lucitta  claim.  The  entire  formation  is  igneous,  bowlders  of 
andesites  being  prominent,  the  intervening  material  being  a 
decomposed  tufa  bleached  by  solfataric  action.  White  beds  of 
leached  metamorphic  shales  are  found  in  these  igneous  masses^ 
and  occasionally  bodies  of  cla3\  In  the  lower  tunnel  (No.  i) 
cinnabar  has  been  deposited  on  the  face  of  the  bowlders  and 
in  the  decomposed  tufa,  occasionally  forming  bunches  of  ore, 
apparently  of  good  grade.  Such  an  ore  body  is  found  in  the 
first  crosscut  [see  Fig.  12].  In  the  middle  tunnel  (No.  2)  the 
country-  rock  is  the  same  as  in  the  lower  tunnel.  The  best  ore 
is  found  in  the  side  drift,  60  feet  long,  running  southeast  and 
branching  from  the  southwest  crosscut  near  breast.  Past  the 
crosscut  the  drift  enters  into  very  hard,  barren  material.  The 
ledge  matter  appears  to  be  a  metamorphic  bleached  shale,  occa- 
sionall}-  gritty;  while  very  much  broken  up,  it  shows  a  tendency 
to  a  stratification  dipping  southwest.  The  material  in  the 
upper  tunnel  (No.  3)  is  principally  decomposed  tufa,  carrying 
some  ore.  The  main  drift  has  caved  at  100  feet  from  the 
mouth,  and  two  cur\'ed  drifts  have  been  run  to  reach  the  terri- 
tory past  the  cave;  the  left-hand  drift  shows  good  ore  in  the 
breast.  The  plan  shows  that  this  ore  lies  above  that  opened 
in  tunnel  No.  3;  hence  this  ore  body  is  probably  continuous  for 
a  depth  of  80  feet.     A  little  higher  up  the  mountain  is  an  open 


LAKE   COUNTY. 


59 


pit,  25  feet  deep.  The  walls  are  formed  entirely  by  decomposed 
and  leached  tufa,  with  bunches  of  cinnabar  ore  all  through  the 
material.  Similar  bunches  of  cinnabar  ore  are  found  in  the 
decomposed  tufa  on  the  hillside  all  over  the  claim,  but  onh^  in 
the  middle  tunnel  a  regular  ledge  is  exposed,  which,  from  the 
appearance  of  the  breast  of  the  left-hand  drift  in  the  upper 
tunnel,  is  probably  covered  up  by  the  cave.     A  small  prospect 


Fig.  12.     Lucitta  Mine. 

opening  near  the  dump  of  tunnel  No.  2  shows  solfataric  action, 
and  formations  very  similar  to  those  at  the  surface  at  Sulphur 
Bank.     The  mine  is  equipped  with  a  lo-pipe  retort  furnace. 

Middletown  Mine. — Mayacmas  District.  In  Sec.  7,  T.  10  N., 
R.  7  W. ;  about  half  a  mile  southwest  of  the  Jewess.  Owner, 
W.  H.  Parsons,  Middletown,  Lake  County.  An  outcrop 
similar  to  that  on  the  Jewess  and  Wall  Street,  on  which  some 
work  has  been  done  on  the  top  of  the  ridge,  showing  a  small 
amount  of  cinnabar  through  the  ledge  matter.  The  countr}^ 
rock  is  nearly  all  serpentine.     About  90  feet  lower  a  tunnel 


60  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

35  feet  long  shows  very  hard,  cherty  material,  carrying  some 
specks  of  cinnabar.  A  crosscut  tunnel  50  feet  long  is  started 
about  200  feet  below  the  upper  croppings  in  very  decomposed 
country  rock,  probably  schist. 

Shamrock  Mine* — Clear  Lake  District.     Owners,  J.  C.  Ansel, 

Sulphur  Creek,  Colusa  County;  J.  B.  Mason  and Swift, 

Knoxville,  Napa  County.  In  Sees.  14  and  23,  T.  13  N.,  R.  6  W. 
It  consists  of  the  Shamrock  and  Shamrock  Extension  claims. 
The  mine  is  on  Rocky  Creek,  a  tributary  of  Cache  Creek,  in  a 
very  extensive  belt  of  serpentine,  which  to  the  southeast 
extends  to  the  Knoxville  district.  Rocky  Creek  makes  a  sharp 
curve  on  the  ground  of  this  mine,  forming  a  narrow  peninsula, 
about  100  feet  above  the  bed  of  the  creek,  which  has  been 
crosscut  by  two  tunnels;  the  one  starting  from  the  up-stream 
side  has  caved  in  and  is  inaccessible;  the  other,  on  the  down- 
stream side,  runs  in  a  course  S.  60°  W.,  first  through  125  feet 
of  shales,  then  75  feet  through  decomposed  serpentine  and 
sandstone  bowlders.  At  this  poin^  drifts  have  been  run 
N.  68°  W.,  and  S.  68°  E.,  mainly  in  gouge;  but  little  ore  can 
be  seen  in  these  drifts. 

Standard  Quicksilver  Company. — Mayacmas  District.  Z.  W. 
Christopher,  superintendent,  Mirabel,  Lake  County.  This 
company  owns  a  large  tract  of  land  in  the  neighborhood  of 
Mirabel,  on  both  sides  of  St.  Helena  Creek.  [See  Mon.  XIII, 
U.  S.  G.  S.,  page  375;  Report  State  Mining  Bureau  of  Cal., 
VIII,  page  325;  XI,  page  64;  XII,  page  360;  XIII,  page  595.] 
The  Mirabel,  formerly  the  Bradford,  which  was  opened  in 
1887  and  at  the  time  was  a  great  producer,  on  the  western 
bank  of  St.  Helena  Creek,  is  considered  worked  out  by  the  pres- 
ent owners.  It  was  abandoned  in  1897,  and  has  filled  with 
water.  The  total  production  of  this  mine  was  30,590  flasks; 
the  greatest  depth  of  the  workings  is  500  feet;  22,500  linear 
feet  of  drifts  were  driven  and  750  feet  of  shaft  sunk.  The 
company  has  as  yet  not  succeeded  in  developing  any  workable 
deposits  east  of  St.  Helena  Creek.  On  the  west  side,  a  little 
to  the  north  of  Mirabel,  in  Sec.  23,  T.  10  N.,  R.  7  W.,the  com- 
pany opened  up  the  Bullion  mine,  nearly  on  a  line  running  from 
the  Mirabel  to  the  Great  Western  mine.  This  mine  is  located 
on  a  ledge  having  a  general  strike  about  north  (N.  8°  \V.) 
and  dipping  to  the  east.     The  dip  of  the  ledge,  rather  steep 


LAKE    COUNTY. 


61 


near  the  surface,  flattens  out  with  depth,  and  consequently 
the  vertical  shaft  started  in  the  hanging-wall  sandstone 
cuts  the  vein  and  enters  the  foot-wall  serpentine.  [See 
Fig.  13.]  The  nature  of  the  hanging-wall  material,  meta- 
morphic  sandstone,  was  ascertained  while  sinking  the  shaft; 
against  the  vein  lies  a  very  wide  belt  of  gouge,  through  which 
no  crosscut  has  been  driven  below  the  450-foot  level.  The 
ledge  varies  sensibly  in  width,  but  its  average  may  be  placed  at 
35  feet.     The   ore  forms  in  ^  ,^^- 

fissures  running  across  the 
vein,  starting  from  the  hang- 
ing wall  and  feathering  out 
toward  the  foot  wall;  some- 
times these  cross  fissures 
occur  close  together  and 
then  .  form  workable  ore 
bodies.  This  ore  formation 
would  indicate  a  secondary 
concentration  of  the  mercury 
from  the  sandstone;  but 
then  the  displacement  which 
caused  the  very  heavy  gouge 
on  the  hanging  wall  must 
have  been  posterior  to  the 
ore  concentration  in  the 
ledge.     Where  the  ledge  is 

barren,  the  opaline  rock  forming  its  filling  is  very  compact. 
The  property  is  equipped  with  a  40-ton  Hiittner  &  Scott 
furnace,  provided  with  a  mechanical  drawing  apparatus,  and 
brick  condensers  provided  with  waterbacks. 

Sulphur  Bank. — Clear  Lake  District.  Empire  Consolidated 
Quicksilver  Mining  Company,  owner;  R.  A.  Boggess,  general 
manager,  Sulphur  Creek,  Colusa  County.  In  Sees,  i,  2,  3,  6,  8, 
II,  12,  13,  17,  18,  and  20,  T.  13  N.,  R.  8  \V.,and  Sec.  14,  T.  13  N., 
R.  7  \V.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  254,  etc.;  American 
Journal  of  Science,  vol.  XXIV,  3d  series,  page  23,  et  seq. ;  Report 
State  Mining  Bureau  of  Cal.,  X,  page  238;  XI,  page  63;  XII. 
page  361;  XIII,  page  597.]  The  Sulphur  Bank  mine  was  opened 
in  1875  and  worked  until  1883,  during  which  period  the  Herman 
shaft  was  sunk.    Work  was  resumed  in  1887  and  continued  until 


Fig.  13.     Section  of  Bullion   Mine  (Standard 
Quicksilver  Company). 


62 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


1 897,  during  which  period  the  Diamond  and  Babcock  shafts  were 
sunk.  In  1 899,  work  was  again  resumed  and  has  been  prosecuted 
until  the  present  time.  The  total  production  of  the  property  has 
been  92,000  flasks,  the  greater  part  being  obtained  from  the  sur- 
face workings.  This  property  has  been  extensively  described  and 
discussed  by  several  geologists,  principally  because  it  afforded 
special  occasion  to  study  the  relations  between  solf  ataric  waters 
and  the  genesis  of  ore  deposits.  In  Mon.  XIII,  U.  S.  G.  S.,  a 
very  detailed  geological  map  of  the  property  is  given. 


PHOTO  No.  3.    WESTERN  CUT— SULPHUR  BANK  MINE. 

The  deposit  may  be  considered  from  two  points  of  view: 
the  surface  developments  and  the  underground  developments. 

The  surface  developments  in  their  present  state  give  the  im- 
pression of  an  abandoned  hydraulic  mine,  there  being  exten- 
sive shallow  cuts,  more  or  less  filled  with  bowlders  of  barren 
igneous  rocks.  [See  photograph  of  Western  cut,  Sulphur  Bank 
mine.]  The  igneous  rock  was  determined  by  W.  Jackson  in 
18S0  as  augite-andesite,  mainly  because  of  the  absence  of 
olivine;  but  in  Mon.  XIII,  above  cited,  it  is  classified  as  basalt. 


Sulphur  Bank  Mine. 


-N  .-'/p'c^'X-'-' 


sp' 


''vl«>jr 


Stt'S 


.<^^ 


^^' 


I 


LAKE    COUNTY, 


63 


and  the  latter  determination  is  generally  accepted.  These 
basalt  bowlders  may  be  a  flow  from  the  craters,  yet  discernible 
to  the  northeast  of  the  bank,  or  may  have  been  ejected  from  a 
vent  close  to  the  bank,  which  has  as  yet  not  been  uncovered. 
Up  to  the  present  time  this  basaltic  flow  has  been  found  every- 
where overlying  the  altered  sedimentaries.  As  the  cinnabar 
deposits  are  not  restricted  to  the  territory  covered  by  the  lava 
flow  at  the  Bank  [see  Fig.  14],  and  as  most  careful  investiga- 
tion has  failed  to  disclose  any  cinnabar  or  mercury  in  the 
undecomposed  basalt,  this  basalt  can  not  be  the  source  of 
the  metal. 

The  upper  crust  of  the  lava  deposit,  to  a  thickness  of  a  few 
feet,  consists  of  a  white  silica,  the  residue  of  the  complete  de- 
composition of  the  basalt,  by  the  combined  action  of  the  highly 


-?a  3<i  I  fSouldt 


arreL   Si'rt.tt.rs 


'3ac/^/<  cCJ3^S«  //i 


Fig.  15.     Sulphur  Bank  Mine— Elevation  of  Upper  Wagon  Spring  Cut  at  (X). 

sulphurous  solfataric  waters  and  the  atmosphere,  forming  sul- 
phuric acid  (H.S  +  40  =  H.SO*),  which  decomposed  all  the 
silicates  in  the  rock  and  left  the  pure  silica.  Immediately 
below  the  surface  zone,  where  oxygen  was  not  so  abundantly 
present,  free  sulphur  was  formed  (H:;S  -f  O  ^  H.O  -f  S).  This 
took  place  to  such  an  extent  that  originally  the  property  was 
worked  for  sulphur.  About  2000  tons  of  sulphur  have  been 
extracted. 

The  basalt  occurs  in  places  as  masses  of  bowlders,  which 
near  the  surface  are  surrounded  by  shells  of  decomposed 
material  of  grayish  color  and  very  much  disintegrated.  Below 
these  bowlders  and  in  places  reaching  very  near  the  surface, 
as  in  the  bank  of  the  Upper  Wagon  Spring  cut  [see  Fig.  14  at 
X  and  Fig.  15]  and  in  the  Apex  cut,  the  basalt  has  a  more  or 
less  bedded  form.  When  first  uncovered,  the  basalt  bowlders 
have  a  rough  surface;  but  when  in  contact  with  the  atmos- 
phere for  a  short  time,  their   outer  shell  readily  decomposes 


64  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

and  disintegrates,  giving  them  a  waterworn  appearance.  The 
neighborhood  of  Sulphur  Bank  is  at  present  a  region  of  great 
solfataric  action,  not  so  intense,  however,  as  in  the  past.  A 
number  of  cuts  have  been  run,  covering  a  territory  2000  feet 
long  and  See  feet  wide,  and  having  a  general  northwestern 
direction.  These  surface  works  are  mostl}'  in  the  territorj- 
covered  by  the  lava  flow,  but  to  the  south,  and  especially  to 
the  southeast  in  the  Wagon  Spring  cut,  near  the  Herman 
shaft,  the  sedimentaries  come  to  the  surface.  Iron,  mosth'  as 
oxide,  is  extensively  found  in  this  surface  zone;  in  places  the 
black  coloring  of  the  material  is  due  to  iron  oxides.  Sulphur, 
as  already  mentioned,  is  also  very  prominent,  in  the  forms  of 
free  sulphur,  metallic  sulphides  and  sulphates,  and  free  sul- 
phuric acid.  Hj'drocarbons,  mostly  in  minute  globules,  are 
also  present.  Mercuric  sulphide  (cinnabar)  is  one  of  these 
metallic  sulphides,  and  occurs  in  many  places  sufficiently  con- 
centrated in  seams  and  pockets  to  form  workable  ore  bodies. 
In  the  bowlder  zone  it  forms  in  the  disintegrated  material  fill- 
ing the  interstices  of  the  bowlders;  in  the  bedded  zone  it 
occurs  in  seams,  which  allowed  the  passage  of  the  ascending 
solfataric  waters,  and  wherein  the  latter  deposited  the  cinnabar 
with  a  more  or  less  gelatinous  opaline  silica. 

Underlying  the  basalt  are  sedimentaries.  It  is  greatly  to  be 
regretted  that  the  management  of  this  property  has  not  taken 
pains  to  preser\-e  geological  descriptions  of  the  underground 
works,  which  are  all  caved  in,  except  the  Empire  shaft,  now  in 
progress  of  sinking.  The  latter  is  so  tightly  timbered,  owing 
to  bad  ground,  that  it  ofiers  no  opportunit}'  to  study  the  forma- 
tions through  which  it  has  passed.  The  following  remarks 
regarding  the  sedimentary  formations  are  only  fragmental  and 
are  collected  from  dift'erent  sources: 

The  sedimentaries  consist  of:  the  Cache  Lake  beds  ( Quater- 
nary- ) ,  conglomerates,  sand  beds,  and  argillaceous  and  calcareous 
deposits,  which  are  generally  very  friable  and  at  Sulphur  Bank 
thoroughly  decomposed  by  solfataric  action.  According  to 
Professors  Le  Conte  and  Rising  these  beds  appear  to  be  more 
tilted  to  the  east,  near  the  Herman  shaft,  and  nearer  to  the 
volcanic  vent  or  vents  than  westward  near  the  Babcock  and 
Diamond  shafts.  Underlying  the  Cache  Lake  beds  are  the 
Lower  Cretaceous,  Xeocomian  rocks,  prominently  sandstones, 
most  highly  metamorphosed.     Professors  Le  Conte  and  Rising 


LAKE   COUNTY.  65 

seem  to  assume  that  the  Cache  Lake  beds  belong  to  the  same 
period  as  these  underl^dng  sandstones,  determined  bj^  Becker 
to  be  Neocomian.  On  the  contact  of  the  Cache  Lake  beds  and 
the  metamorphosed  sandstone  is  found  a  brecciated  zone,  which 
in  the  neighborhood  of  the  Herman  shaft  appears  to  be  tilted 
at  a  steep  angle,  dipping  southward.  On  the  line  of  cross- 
section  A  B  [see  Fig.  14],  the  contact  is  also  dipping  south 
between  the  Babcock-Diamond  line  and  the  Empire  shaft,  but 
only  at  an  angle  of  about  30°.      [See  cross-section  C  D.] 

Taking  low  water  in  Clear  Lake  as  datum,  the  depth  of  the 
contact  in  the  shafts  is:  Empire  shaft,  185  feet;  Babcock  shaft, 
100  feet;  Diamond  shaft,  90  feet. 

The  Quaternary  beds  are  highly  siliceous  and  interbedded 
with  strata  of  very  loose  material,  acting  as  quicksand,  disinte- 
grated by  the  percolating  solfataric  waters.  In  the  Wagon 
Spring  cut  where  they  appear  at  the  surface,  the  brecciated 
zone,  consisting  of  fragments  of  shale  and  sandstone  inclosed 
in  a  claye}'  material,  formed  a  channel  for  the  ascending  solfa- 
taric waters,  which  deposited  therein  cinnabar  and  pyrites. 
This  deposit  will  be  discussed  hereafter  in  this  chapter. 

A  great  number  of  short  tunnels,  drifts,  and  winzes  have 
been  run  in  the  banks  of  the  cuts,  and  shallow  shafts  have  been 
sunk  in  their  bottoms,  to  excavate  pockets  of  cinnabar  ore.  In 
nearly  every  bank  of  the  cuts  formation  of  cinnabar  is  taking 
place  at  the  present  time.  Often,  when  breaking  down  the 
cinnabar-carrying  surface,  no  signs  of  cinnabar  are  found  in 
the  uncovered  surface.  This  formation  of  cinnabar,  which  can 
not  be  an  exudation  product,  may  be  explained  by  the  fact 
mentioned  b}-  Becker  (Mon.  XIII,  page  260)  that  the  waters 
at  the  surface  contain  small  quantities  of  mercuric  sulphide  in 
suspension,  but  none  in  solution,  caused  b}'  the  presence  of 
ammonia.  These  suspended  particles  will  be  deposited  on 
arriving  at  the  surface.  In  the  Western  cut  a  deposition  of 
cinnabar  occurs,  which,  in  the  writer's  opinion,  can  not  be 
explained  except  as  a  deposition  from  mercurial  vapors.  In 
this  cut  a  small  shaft  12  feet  deep  was  sunk,  but  had  to  be 
abandoned  on  account  of  the  peculiar  gas  occasionally  occur- 
ring in  quicksilver  mines,  especially  attacking  the  eyes  of  the 
men,  blinding  them  temporarily  with  intense  suffering.  (Some 
claim  this  gas  to  be  methane.)  [See  also  Great  Eastern  Mine.] 
5— QR 


66  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

Near  this  shaft  ver}-  hot  gases  emanate  from  the  floor  of  the 
cut  and  form  incrustations  on  a  bowlder  of  basalt  lying  in  the 
proximity.  These  incrustations  on  the  top  of  the  bowlder  show 
signs  of  cinnabar,  which  can  not  come  from  any  other  source 
than  from  these  gases. 

In  the  same  cut  not  20  feet  interdistant,  are  two  springs,  one 
cold,  the  other  hot,  from  both  of  which  gases  are  constantly 
emanating,  which  would  tend  to  indicate  that  the  gases  and 
waters  are  not  derived  from  the  same  source.  The  depth  of 
the  surface  workings  has  been  limited  by  the  water  level.  Shal- 
low shafts  prove  that  cinnabar  occurs  below  the  floor  of  the 
cuts  as  well  as  in  their  banks;  but  the  relation  between  the 
cinnabar  occurrence  at  the  surface  and  that  underground  has 
as  yet  not  been  clearly  established. 

The  territorj^  developed  by  the  underground  workings  does 
not  underlie  that  developed  by  the  surface  workings,  except 
for  a  slight  portion  near  the  Herman  air  shaft,  and  is  much 
more  restricted  than  the  surface  workings.  [See  Fig.  14.] 
Unfortunately  all  the  old  shafts  have  caved  and  are  inaccessi- 
ble. The  Empire  shaft,  in  process  of  sinking,  has  been  started 
with  the  purpose  of  reaching,  by  drifting,  ore  bodies  presumed 
to  exist  under  the  Western  cut;  these  drifts  will  have  to  run 
through  the  ground  underlying  the  caved-in  stopes  of  the 
Diamond  shaft.      [See  below.] 

The  Herman  shaft  is  geologically  the  most  interesting,  as  in, 
these  works  connection  might  be  traced  between  surface  and 
underground  phenomena.  The  details  available  at  the  mine 
are  very  deficient,  but  a  description  of  the  works  in  this  shaft 
in  1880  and  1881  is  found  in  the  above-cited  article  by  Profes- 
sors Le  Conte  and  Rising,  from  which  the  following  is  quoted: 
"The  upper  level,  210  feet,  runs  (in  a  course  about  N.  60*^  W. ) 
"from  70  to  80  feet  in  barren  sandstone  and  shale,  dipping 
"about  south,  the  rock  being  comparatively  dry  and  cool;  then 
"cuts  through  a  breccia,  carrj'ing  a  great  amount  of  hot  waters, 
"containing  considerable  alkaline  sulphides,  carbon  dioxide, 
"and  hj'drogen  sulphide;  temperature,  160°  F.,  with  ver}'  strong 
"emanations  of  carbon  dioxide.  This  breccia  contained  the 
"ore.  The  level,  of  a  total  length  of  232  feet,  cut  through  this 
"ore  body  and  reached  barren  ground." 

The  plans  of  the  works  [see  Fig.  16]  show  a  second  smaller 
ore  body,  not  mentioned  in    above  description.     Becker,  who 


LAKE    COUNTY. 


67 


visited  the  shaft  in  1887,  states  (Mon.  XIII,  page  263):  "An 
"important  ore  body  was  followed  down;  *  *  *  the  shaft 
"is  417  feet  deep,  with  seven  levels.  *  *  *  This  body  has 
"been  worked  out,  and  only  the  lowest  portion  was  accessible. 
"The  small  amount  of  ore  remaining  consisted  of  partially 
"metamorphosed  sandstones  and  shales  carrying  small  stringers 
"of  cinnabar,  quartz,  and  pyrite.     I  was  not  able  to  get  satis- 


f  6^ 


ML 


^W 


Fig.  16.     Sulphur  Bank  Mine — Section  and  plan  of  Herman  shaft. 


"factor}'  information  as  to  the  depth  from  the  surface  of  the 
"contact  between  the  Lake  deposits  and  the  brecciated  meta- 
"morphic  sandstones  and  shales." 

The  above  quoted  article  of  Le  Conte  and  Rising  continues: 
"The  lower  level,  260  feet,  reached  the  ore  body  at  136  feet 
"from  the  shaft.  The  varying  dips  on  the  different  levels  show 
"that  the  strata  are  very  much  broken  up.  The  brecciated 
"layer,  which  as  in  the  Wagon  Spring  cut  is  composed  of  frag- 


^^V  >V^    Shale. 


Cinnabar 
ore. 


68  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

"ments  of  shale  and  sandstone,  forms  also  here  the  water 
"channel.  Where  the  ascending  water  is  abundant,  the  matrix 
"is  hot  mud;  where  the  rock  is  drier,  this  has  changed  into  a 
"paste  containing  disseminated  metallic  sulphides,  or  into  a 
"regular  indurated  deposit  from  solfataric  waters.  The  spaces 
"between  the  fragments  are  sometimes  only  partially  filled; 
"the  lining  of  the  cavities  is  generally  cinnabar,  sometimes 
"pyrites,  or  silica,  or  all  of  them;  the  silica  grading  from  chal- 
"cedonic  into  gelatinous.  [See  Fig.  17.]  The  ore  deposit  is 
"  not  entirely  confined  to  the  breccia.    Its  form  is  ver}-  irregular; 

"sometimes  ore  bodies 
"are  separated  b}-  bar- 
"ren  rock,  sometimes 
"they  enter  the  shat- 
"tered  sandstone,  leav- 
"ing  the  breccia.  No 
"free  sulphur  is  found 
"  in  the  ore  bodies.  The 
"  irregularity'  of  the  ore- 
"  bearing  fissures  shows 
"  that  the  shattering  ef- 
"fects  were  not  confined  to  the  brecciated  strata." 

Comparing  this  ore  occurrence  with  that  at  the  surface  in 
Wagon  Spring  cut,  near  the  Herman  air  shaft,  which  is  found 
in  a  soft  brecciated  stratum  several  feet  wide,  consisting  of 
fragments  of  shale  and  sandstone  with  a  matrix  of  blue  clay 
mud,  through  which  hot  alkaline  waters  at  125^  F.,  highly 
charged  with  hydrogen  sulphide  and  carbonic  and  boracic 
acids,  are  ascending,  and  in  which  considerable  cinnabar  and 
pyrites  have  been  deposited,  the  conclusion  is  that  both 
deposits  have  probably  the  same  genesis,  though  their  relation 
is  not  clearly  established. 

The  following  part  of  the  quotation  cited  above  from  Mr. 
Becker's  work:  "I  was  not  able  to  get  satisfactory  information 
*  *  *  of  the  contact  between  the  Lake  deposits  and  the  meta- 
morphic  sandstone  and  shale,"  indicates  that  in  his  opinion  the 
formation  at  the  surface  in  Wagon  Spring  cut  belongs  to  the 
lake  beds.  No  underground  ore  bodies  have  been  found  in 
these  beds,  possibh^  due  to  the  fact  that  these  beds  offered  a 
greater  number,  but  more  minute  channels  to  the  waters,  and 


Fig.  17.    Sulphur  Bank  Mine— Ore 
formation  in  Herman  shaft. 


LAKE    COUNTY. 


69 


the  ore  deposition  was  subsequently  less  concentrated:  for  it 
may  be  accepted  as  a  fact  that  the  cinnabar  deposits  at  the 
surface  and  underground  belong  to  the  same  system  of  water 
circulation. 

From  the  accompanying  section  of  the  Diamond  shaft  [see 
Fig.  1 8]  it  may  be  concluded  that  here  the  lake  beds  overlie 
the  metamorphic  shales  and  sandstones  [see  also  sections  on 
Fig.  14],  rendering  the  assumption  that  such  is  the  case  in  the 
Herman  shaft  all  the  more  probable.  The  material  at  the  sur- 
face in  the  Wagon  Spring  cut  is  so  thoroughly  decomposed 
that  it  is  impossible  to  decide  this  question  by  its  study. 

The  accompanying  sketch  of  the  old  works  of  the  Diamond 
shaft  [see  Fig.  18]  shows  the  ore  body  in  the  metamorphic 
sandstones  underlying 
the  surface  formations. 
Judging  from  the  plans, 
the  ore  body  was  in 
places  40  feet  wide.  It 
is  reported  that  at  the 
time  the  shaft  collapsed 
the  lower  level  had  not 
reached  the  limits  of 
the  ore  body.  Includ- 
ing the  results  of  the 
workings  of  the  Bab- 
cock  shaft  (also  col- 
lapsed), the  length  of 
this  ore  body  may  be 
placed  at  500  feet;  but 

it  is  doubtful  if  any  of  this  ground  will  be  available  in  the 
future  because  of  the  collapse  of  both  shafts,  as  this  treacher- 
ous ground  is  saturated  clear  to  the  surface  with  hot  acidic 
waters.  Xo  data  are  available  to  judge  whether  the  ore 
formed  in  a  brecciated  contact  zone,  or  in  fractures  cutting 
through  strata;  in  other  words,  whether  the  ore  bodies  resem- 
bled the  upper  part  of  the  deposit  in  the  Herman  shaft,  as 
described  by  Le  Conte  and  Rising,  or  the  lower  part,  as 
described  by  Becker. 

The  breccia  in  the  Diamond  and  Empire  shafts,  judging 
from  dump  samples,  appears  to  be  a  fragmental  sandstone 
recemented  by  silica,  which,  being  softer,  offered  more  favor- 


A7e/^pt7.  ^.S/or^e^ 


Sulphur  Bank  Mine— Section  of 
Diamond  shaft 


70  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

able  conditions  for  ore  deposition  than  the  more  compact  meta- 
morphic  sandstone.  If,  as  it  appears  to  do  in  the  Empire  shaft, 
the  formation  becomes  more  compact  in  depth,  the  ore  deposits 
will  probably  accordingly  decrease  in  value. 

Summarizing,  it  may  be  stated  that  deposition  from  solfa- 
taric  waters  is  the  prominent  mode  of  ore  formation,  but  that 
mercurial  vapors  are  present  and  probably  play  their  part  in 
this  process.  The  solfataric  waters  are  highly  charged  with 
active  chemical  agents,  but  the  source  from  whence  they  derive 
their  mercuric  contents  is  at  present  unknown;  the  igneous 
bodies,  however,  to  which  the  basalt  surface  flow  belongs,  are 
certainly  not  the  source  thereof. 

The  increase  in  heat  with  depth  in  the  Herman  shaft  is 
worthy  of  note.  At  the  surface,  128°  F. ;  at  200  feet  depth, 
160"  F. ;  at  about  300  feet,  176°  F.  Assuming  the  surface  heat 
of  128°  F.,  those  at  200  and  300  feet  depth,  according  to  the 
general  rule  of  increase  by  static  influence,  would  be  respec- 
tively 132°  and  134°  F.  This  shows  that  in  regions  of  solfa- 
taric action  the  increase  in  heat  with  depth  is  extremely  rapid, 
and  that  conclusions  regarding  physico-chemical  phenomena 
must  take  this  rapid  rate  of  increase  into  account,  even  for 
zones  of  shallow  depths. 

The  great  heat,  the  chemical  composition  of  the  underground 
waters  and  gases,  and  the  character  of  the  rock,  render  the 
underground  exploration  of  this  property  a  ver}'  serious  under- 
taking. 

This  property  is  equipped  with  four  furnaces,  of  which  one 
is  a  Knox  &  Osborne  25-ton  furnace,  the  others  are  Hiittner  & 
Scott  furnaces,  respectively  of  40,  17,  and  30  tons,  and  with  a 
furnace  having  nine  q  retorts. 

Thorn  Mine. — Mayacmas  District.  In  Sec.  36,  T.  11  N., 
R.  8  W.  On  the  north  side  of  Bear  Creek,  south  of  Anderson 
Springs.  Owner,  D.  H.  Thorn,  Anderson  Springs,  Lake 
County.  This  prospect  lies  very  close  to  the  top  of  the  ridge. 
Near  the  surface  some  pockets  of  good  ore  were  found,  but 
did  not  continue  in  depth.  The  underground  works,  60  feet 
below  the  upper  works,  show  as  yet  no  ore  at  all,  and  in  the 
upper  works  the  ore  bodies  pinched  out  at  a  ver}-  slight  depth. 

Utopia  Mine.— Clear  Lake  District.  In  Sec.  25,  T.  13  N., 
R.  6  W.,  about  opposite  Lakeport,  near  the  east  shore  of  Clear 


LAKE    COUNTY. 


71 


Lake.  The  Utopia  Quicksilver  Min- 
ing Compan)',  owner;  M.  S.  Sayre,  of 
Lakeport,  president.  [See  Report 
State  Mining  Bureau  of  Cal.,  XIII, 
P^ge  597-]  The  company  is  con- 
templating opening  this  mine. 

Wall  Street  Mine, — Mayacmas  Dis- 
trict. In  Sec.  I,  T.  lo  N.,  R.  8  \V. 
Owner,  W.  H.  Parsons;  postoflfice, 
Middletown,  Lake  County.  [See 
Mon.  XIII,  U.  S.  G.  S.,  page  375; 
Report  State  Mining  Bureau  of  Cal., 
XII,  page  362.]  The  former  owners 
spent  considerable  mone)'  in  explora- 
tion works,  without  satisfactory  re- 
sults. Their  old  workings  are  largely 
caved  in,  the  fur- 
nace is  destroyed 
and  its  site  prac- 
tically obliterated. 
In  an  old  tunnel 
(2440  feet  eleva- 
tion) [see  Fig.  19] 
there  is  a  ledge 
of  hard  siliceous 
rock,  carrying 
some  metal  along 
a  seam,  and  pen- 
etrating from  that 
seam  into  the 
small  fractures  of 
the  rock,  forming 
a  poorly  mineral- 
ized zone  about 
18  inches  wide, 
with  a  strike 
northwest,  and  a 
southwesterly 
dip,  which  shows, 
however,  only 
over  a  length  of 
40  feet,  and  about 
50  feet  along  the 


72 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


dip.  This  mineralized  zone  is  apparently  cut  off  to  the  east  bj' 
a  body  of  hard,  compact  serpentine,  and  has  not  been  found 
past  this  point.  Both  walls  are  serpentine,  and  there  is  no 
gouge  on  either  wall.  It  appears  as  if  a  vein  has  cut  through 
the  point  of  the  hill,  and  only  carried  metal  in  the  eroded 
dome.  The  eastern  branch  directs  toward  the  workings  of  the 
Jewess,  which  have  proven  barren. 

NAPA  COUNTY, 

Aetna   Consolidated   Quicksilver    Mines. — Mayacmas    District. 
In   Sees.    2,   3,   and  4,  T.  9  X.,  R.  6  \V.     Owner,  The  .Etna 


/JETN/l      CON.      MINES. 


ONB     MILE 


Fig.   20.     ^tna  Consolidated  Mines. 

Consolidated  Quicksilver  Mining  Company-,  70  Kilby  street, 
Boston,  Mass.;  B.  M.  Newcomb,  Oathill,  Napa  County,  Super- 
intendent. [See  Mon.  XIII,  U.  S.  G.  S.,  pages  354,  371 ;  Report 
State  Mining  Bureau  of  Cal.,  XI,  page  72;  XII,  page  362; 
XIII,  page  597.]  This  group  of  mines  is  situated  at  the 
southeast  end  of  the  belt  as  at  present  developed.  [See  Fig. 
20.]  It  comprises  the  Phcenix,  Silver  Bow,  Red  Hill.  Star, 
Pope,  and  Washington    mines.     These    mines  were    formerly 


74  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

large  producers,  but  in  the  last  few  years  have  produced  no 
quicksilver.     The  property  can  hardlj'  be  described  as  lying  in 

^/  9  oo'J 


t^af->  ^/j/-a^£ , 


I  itS'oo'J  _ 


Tur-  ri  a./  A^'  /. 


-^/vr 


Fig.  21.    .5itna  Consolidated  Mines — Elevation  at  mouth  of  Tunnel  Xo.  2. 

James  Creek  canon  [Mon.  XIII,  U.  S.  G.  S.,  page  374],  but 
would  be  more  properh'  described  as  located  on  the  northern 
slope  of  a  ridge  running  in  a  northeasterly  direction  from  the 
Twin  Peaks  and  capped  by  lava. 


■^v. 


Ta// 


Fig.  22.     .Etna  Consolidated  Mines— Basalt  dike.  Silver  Bow  claim. 

The  serpentine  in  this  region  appears  to  be  underlaid  by 
sandstone  [see  Fig.  21],  being  a  break  above  tunnel  No.  2  in 
the  Phoenix  claim.  Tunnel  Xo.  7  runs  toward  a  basalt  dike, 
which  breaks  through  to  the  surface,  and  reaches  the  contact 
at  a  depth  of  from  See  to  1000  feet.     This  dike  shows  at  the 


NAPA    COUNTY, 


75 


surface  for  a  length  of  about  I ooo  feet;  the  underground  works 
which  run  around  the  dike  show  it  to  be  surrounded  by  sand- 
stone. [See  Fig.  22.]  The  basalt  is  cut  of^  at  the  surface  by 
the  same  serpentine  showing  in  Fig.  21 ;  but  from  the  fact  that 
the  latter  does  not  go  through  the  sandstone,  the  surface 
indications  are  not  convincing  that  this  basalt  dike  does  not 
connect  with  the  main  seat  of  eruption,  having  uplifted  the 
serpentine  and  broken  through  the  sandstone.  The  tufa  sur- 
rounding the  basalt  is  more  siliceous  and  probably  older  than 
the  basalt.  It  overlies  the  sandstone  but  not  the  serpentine, 
confirming  the  above  supposition.  The  tufa  overlying  the 
serpentine  has  prob- 
ably been  eroded. 
For  some  reason,  in 
this  region  the  tufa 
is  invariably  found  j 
overlying  the  sand- 
stone but  not  the 
serpentine.  In  the 
Star  claim  another 
short  dike  of  basalt, 
about  100  feet  long, 
has  been  followed  at 
its  contact  with  the 
sandstone  to  a  depth 
of  600  feet. 

The  Washington 
shaft  disclosed  a 
boss   of    serpentine, 

which  carried  a  good  body  of  ore,  while  in  the  sandstone  but 
little  ore  was  found.  [See  Fig.  23.]  In  the  Phoenix  workings, 
at  tunnel  No.  9,  only  sandstone  was  found  underground  in 
the  Red  Hill  claim,  while  the  surface  of  that  claim  is  almost 
entirely  covered  by  serpentine  and  its  allied  opaline  rock;  a 
winze  sunk  from  this  tunnel  follows  a  contact  between  igneous 
rock  and  sandstone  to  a  depth  of  1000  feet. 

All  the  sandstone  in  this  neighborhood  contains  some  cinna- 
bar disseminated  through  it;  but  so  far  workable  ore  deposits 
have  only  been  found  near  the  igneous  rocks  and  the  serpen- 
tine, indicating  a  secondary  concentration  in  connection  with 
the  igneous  rocks  and  the  serpentine. 


^^tna  Consolidated  Mines — Section  of 
Washington  shaft. 


76  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

The  company  is  at  present  doing  prospecting  work,  in  order 
to  determine  whether  workable  ore  bodies  can  be  found  on  the 
contact  with  the  large  dike  on  the  Silver  Bow  claim  above 
described.      [vSee  Fig.  22.] 

Bella  Union  Mining  Company. — This  property  is  in  Sees. 
20  and  28,  T.  7  X.,  R.  5  \V.,  one  and  a  half  miles  south  of 
Oakville.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  377:  Report  State 
Mining  Bureau  of  Cal.,  XII,  pages  364  and  365;  XIII,  page 
599] 

Boston  Mine  (formerly  the  Redington). — Knoxville  District. 
Boston  Qviicksilver  Mining  Company,  owner.  B.  M.  Xewcomb, 
general  superintendent,  Oathill,  Napa  County:  J.  B.  Mason, 
superintendent,  Knoxville,  Napa  County.  In  Sees.  6  and  7, 
T.  II  N.,  R.  4  W.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  284; 
Report  State  Mining  Bureau  of  Cal.,  XI,  pages  69-72;  XII, 
page  363;  XIII,  page  599.]  The  Redington  Quicksilver  Min- 
ing Company  supposedly  worked  out  the  ground  in  the  origi- 
nal shaft  and  abandoned  the  works  in  1882.  In  1890  Mr. 
McMillan  started  on  a  narrow  seam  of  cinnabar  several  hundred 
feet  northwest  of  this  shaft  in  the  serpentine  formation,  which 
upon  development  showed  so  profitable  that  the  northwest 
shaft  was  sunk  and  this  territory  worked  until  1S98.  The 
present  owners  have  reopened  and  retimbered  the  old  shaft, 
and  by  a  systematic  exploration  not  only  found  some  good  ore 
bodies  in  the  foot-  and  hanging-wall  veins,  but  also  opened  up 
large  ore  bodies  in  the  serpentine  lying  in  the  inter\-ening 
territory.  This  vein  has  supplied  the  majority  of  the  ore 
which  the  present  company  has  passed  through  its  furnace, 
and  shows  at  present  large  ore  reserves.  The  result  proves 
again  the  great  importance  of  systematic  exploration  work  in 
a  quicksilver  mine. 

The  ore  bodies  in  this  mine  form  in  the  same  serpentine 
which  runs  along  the  southwestern  border  of  the  mineralized 
zone  of  the  Manhattan  mine.  This  belt  extends  for  several 
miles  to  the  southwest,  but,  except  at  its  contact  with  the  Neo- 
comian  at  Knoxville,  does  not  contain  a  single  ore  body  of  any 
consequence.  The  mineralized  zone  of  the  Boston  mine  has  a 
northwest  strike,  and  dips  at  about  45°  to  the  northeast.  Its 
cross-section  is  given  in  Fig.  24. 

In  the  Neocomian   sandstone,  about   1200  feet  northeast  of 


NAPA    COUNTY.  /  / 

the  ore  zone,  some  work  has  been  done,  confirming  the  fact 
that  cinnabar  forms  in  the  sandstones;  tests  of  the  latter  taken 
from  various  places  indicate  that  cinnabar  is  disseminated  all 
through  this  lormation.  Combining  this  fact  with  the  absence 
of  cinnabar  in  the  serpentine,  even  when  in  close  proximity 
to  the  igneous  rocks  in  the  Manhattan  ground,  and  with  the 
fact  that  in  the  Boston  mine  the  workable  ore  bodies  are  in 
the  serpentine,  the  suggestion  offers  itself  that  the  genesis  of  ore 


PHOTO  No.  5.     BOSTON  QUICKSILVER  MINK. 

formation  in  this  mine  is  similar  to  that  in  the  ^tna  mine — 
secondary  concentration  of  the  ore  disseminated  in  the  sand- 
stones connected  in  some  way  with  the  serpentine  and  igneous 
rocks.  While,  as  far  as  known,  no  igneous  rocks  are  present 
in  this  mine,  basalt  is  known  to  extrude  within  half  a  mile 
from  it,  and  it  is  very  probable  that  intrusions  of  igneous  rocks 
or  laccolitic  bodies  may  have  influenced  the  concentration  in 
conjunction  with  the  serpentinization  process.  This  supposi- 
tion finds  confirmation  in  the  fact  that  deposits  from  solfataric 
springs  can  be  traced  from  the  Manhattan  to  the  Boston  mine. 


78 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


The  intense  chemical  actions  which  have  undoubtedly  taken 
place  in  this  zone,  and  the  great  amount  and  variety  of  sulphur 
compounds  found  therein,  indicate  undoubtedly  close  connec- 
tion with  igneous  actions,  and  can  hardly  be  attributed  exclu- 
sively to  the  reducing  agency  of  organic  matter  or  ferrous  salts 
on  waters  carr^-ing  sulphites  or  sulphates  in  solution.  [See 
Genesis  of  Ore  Deposits,  pages  34S-350.] 

The  mine  is  opened  by  two  shafts.  The  original  shaft,  in 
which  the  works  are  at  present  prosecuted,  is  on  the  southeast- 
ern part  of  the  mineral  zone  near  the  furnace.  This  shaft  is 
600  feet  deep,  but  the  lowest  level  at  present  in  operation  is  at 
390  feet.  Below  that  level  the  works  are  under  water.  The 
second  shaft  is  640  feet  northwest  of  the  furnace,  and  has  been 
sunk  to  a  depth  of  400  feet. 


Fig.  24.     Boston  Miue — Section  over  the  mineralized  zone. 


Footwall  vein  in  opaline. 
Narrow  stratum  of  claj-. 
Serpentinized  breccia  (20-40  ft.). 
Silicified  serpentine  100-200  ft.  wide,  inclosing 
ore  bodies  forming  the  "  serpentine  vein." 


Decomposed  serpentine. 

Hanging-wall  vein. 

Clay. 

Shales  100-200  ft.  ^de. 

Sandstones  carrs-ing  some  cinnabar. 


The  three  parallel  veins  can  be  said  to  be  inclosed  in  serpentine, 
for  the  clay  on  the  hanging-wall  vein  shows  by  its  structure  to 
be  decomposed  serpentine.  The  gangue  in  the  hanging-wall 
vein  is  more  or  less  decomposed  opaline.  That  of  the  foot- 
wall  vein  is  also  opaline,  but  much  less  decomposed.  The  ser- 
pentine of  the  central  vein  is  silicified.  The  ore  forms  in  the 
multitudinous  seams  traversing  the  serpentine,  mainh'  in  a 
direction  parallel  to  the  general  northwest  strike  of  the  zone. 
The  ore  shoots  in  the  vein  are  very  persistent  in  depth  as  far 
as  opened  up,  and  up  to  200  feet  long.  The  vein  fillings  being 
all  siliceous,  the  cinnabar  deposition  is  probably  related  to  this 
silicification.  The  entire  mineral  zone  is,  however,  also  highly 
permeated  with  sulphur.  In  various  places  in  the  mine  con- 
siderable exudations  of  sulpho-salts  are  found.  Iron  pyrites 
are  also  very  prominent  in  the  fissures,  especially  in  or  close  to 


NAPA    COUNTY.  /y 

the  cinnabar  deposits.  Experience  therefore  shows  that  con- 
siderable contents  of  iron  pyrites  indicate  the  proximit}'  of 
bodies  of  cinnabar  ores.  The  cinnabar  occurs  generally  in 
crystal  form,  often  columnar.  Occasional!}'  acicular  crystals 
are  found  in  the  vugs.  Some  metacinnabarite  is  found,  gen- 
erally as  coating  of  iron  pyrite  aggregates.  The  mine  is 
equipped  with  a  6o-ton  Hlittner  &  Scott  furnace. 

Corona  Mine. — Mayacmas  District.  In  Sees.  32  and  33, 
T.  10  N.,  R.  6  W.  [See  Report  State  Mining  Bureau  of  Cal., 
XIII,  page  597.]  The  Vallejo  Quicksilver  Mining  Company, 
owner;  J.  B.  McCauley,  president  and  superintendent,  Oathill, 
Napa  County.  The  mine  is  at  the  head  of  James  Creek,  on  the 
contact  of  a  serpentine  belt  and  the  Oathill  sandstone  for- 
mation. [See  Fig,  25.]  The  ore  occurs  in  a  zone  of  black 
chert  rock,  Ij'ing  between  a  sandstone  foot  wall  and  probably 


'c/f  f  ot^r /^ /y  ■i'faC     S  en-/:>f>-j^  Z^-'-'-e       '- — ^         - 


^ 


in^ 


/S' tT'  J'tV/  S    ^ 


Fig.  26.     Corona  Mine — Section  showing  formation.    Dip,  S.W.  30*. 

a  serpentine  hanging  wall.  [See  below.]  The  general  strike 
of  the  zone  is  N.  45°  W.  Three  ore  shoots  show  at  the  sur- 
face. The  development  consists  mainly  in  a  level  which  enters 
the  hill  running  very  nearly  west  and  crosscutting  the  sand- 
stone foot  wall  for  about  400  feet.  The  sandstone  is  here 
mixed  with  some  shales.  At  400  feet,  the  tunnel  cuts  the  vein 
and  follows  it  about  800  feet  to  the  southeast,  and  1 300  feet  to 
the  northwest.  The  tunnel  cuts  the  vein  at  the  southeasterly 
ore  shoot,  with  about  130  feet  of  backs.  The  workable  ore 
body  is  here  from  10  to  15  feet  wide,  the  cinnabar  forming  in 
fissures  running  through  the  opaline  rock.  Underlying  the 
latter  is  a  white  talc,  wherein  pieces  of  white  and  gray  rock 
are  found,  determined  as  phthanite,  indicating  that  originally 
a  body  of  shales  overlaid  the  sandstone  and  were  silicified, 


80  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

probably  by  the  same  solution  which  formed  the  overlying 
chert  beds.  [See  Fig.  26.]  This  ore  shoot  has  in  the  past  pro- 
duced some  rich  ore,  but  at  present  no  work  is  being  done  upon 
it;  the  development  work  being  centralized  on  the  middle  ore 
shoot,  which  the  tunnel  cuts  at  a  depth  of  350  feet  below  the 
surface.  A  vertical  shaft,  100  feet  deep,  has  been  sunk  from 
the  tunnel  level  on  this  shoot.  The  tunnel  is  driven  northwest 
to  cut  the  third  ore  shoot.  Part  of  the  tunnel  is  run  in  the 
sandstone  foot  wall,  determining  its  persistency,  but  no  cross- 
cut has  been  run  into  the  hanging  wall.  A  ver}^  soft  decom- 
posed material  overh-ing  the  ore  body  was  crosscut  to  a  width 
of  35  feet,  without  finding  unaltered  material;  hence  the 
assumption  of  a  serpertine  hanging  wall  rests  on  surface  indi- 
cations. The  black  chert  wherein  the  ore  makes  is  from  40  to  45 
feet  wide;  it  has  a  verj'  irregular  bedding  system,  which,  if 
any,  may  be  said  to  be  a  little  more  prominent  across  the  vein, 
but  the  higher  mineralized  portions  seem  to  follow  the  trend 
of  the  ledge.  The  central  ore  shoot  has  been  opened  for  a 
length  of  160  feet,  and  has  been  persistent  in  depth  from  the 
surface  to  the  present  depth  of  450  feet.  The  cinnabar  forms 
occasionally  in  such  hard  and  compact  material  that  it  can 
scarcely  be  understood  how  it  found  access  10  its  place  of  depo- 
sition. There  is  no  apparent  difference  between  the  barren 
and  the  cinnabar-bearing  chert;  the  former  may  be  in  its 
general  texture  a  little  more  compact.  A  special  feature  of 
this  mine  is  the  very  great  amount  of  sulphide  of  iron  accom- 
panying the  cinnabar.  The  furnace,  of  50  tons  capacity,  is 
ver}'  much  like  an  ordinar}-  Scott  furnace;  the  ore  is  so  highly 
pyritous  that  very  little  fuel  is  required.  This  feature  has  the 
objection  that  the  heat  in  the  furnace  is  ver}-  irregular,  and 
generalh-  far  too  high,  entailing  a  great  loss  of  mercurj-. 

La  Joya  Mines. — The  Standard  Consolidated  Quicksilver  Min- 
ing Company,  owner.  The  property  is  in  Sec.  24,  T.  7  N., 
R.  6  W.,  three  miles  southwest  of  Rutherford.  These  mines 
have  been  idle  for  several  years  and  the  works  are  caved  in. 
Regarding  La  Joya  mine,  Mr.  von  Leicht  reported  in  March, 
1S98,  three  known  ore  bodies,  separated  by  barren  stretches, 
in  an  altered  serpentine,  cropping  at  the  surface  as  yellow 
ochery  matter,  on  the  contact  of  sandstone  and  serpentine  to 
the  southwest  of  the  former;  strike  northwest.     The  gangue 


NAPA    COUNTY. 


81 


minerals  as  reported  are:  silicates  and  calcites,  no  iron  pyrites 
or  sulphur.  Since  this  report  was  made  some  further  explora- 
tion work  had  been  done.  A  20-ton  Fitzgerald  furnace  has 
been  erected,  but  not  used  as  yet. 

Manhattan  Mine.— Knoxville  District.  Lake  Mining  Com- 
pany, owner;  R.  B.  Knox,  Knoxville,  Napa  County.  In  Sec. 
6,  T.  II  N.,  R.  4  W.,  and  Sec.  i,  T.  11  N.,  R.  5  W.  [See  Mon. 
XIII,  U.  S.  G.  S.,  page  282:  Report  State  Mining  Bureau  of 
Cal.,  XI,  pages  70-72;   XII,  page  363;  XIII,  page  598.]     The 


PHOTO  No.  0.     MAXH.\TTAX  Ql'ICKSILVER  MINE. 

first  work  on  this  mine  was  performed  at  Johntown  in  1863. 
[See  Fig.  27.]  As  the  ore  was  reduced  at  the  Redington  mine 
its  product  was  credited  to  that  property.  Work  was  resumed 
in  1 868  until  1877,  then  the  mine  was  idle  until  1884,  but  has 
been  in  constant  operation  since  that  year.  Total  production, 
about  1 5,000  flasks. 

The  study  of  this  mine  is  especially  interesting  in  regard  to 
the  relation  of  igneous  rock  and  the  ore  deposition.  The  ore 
deposits  are    found  in  a  belt  having  a  general  northwestern 

6— QR 


82  QUICKSILVER    KESOURCES   OF   CALIFORNIA. 

direction,  lying  between  basalt  to  the  northeast  and  serpentine 
to  the  southwest.  The  basalt  does  not  show  at  the  surface  in 
a  continuous  line;  the  full  red  line  on  the  plan  of  the  mine 
represents  as  nearly  as  possible  the  line  of  its  vent.  The  ter- 
ritory between  the  basalt  and  the  serpentine  is  almost  entirely 
covered  b}'  tufa,  except  in  the  following  places : 

At  Johntown  is  a  small  exposure  of  the  "mudrock"  in 
which  the  original  discovery  of  cinnabar  in  this  mine  was 
made. 

North  of  the  furnace  and  close  to  the  serpentine  lies  a  large 
body  of  chalcedony,  formed  most  probably  by  mineral  springs. 

On  the  northwestern  end  of  the  property  is  found  the  hill 
represented  by  section  3,  showing  a  body  of  serpentine  almost 
entirely  covered  by  tufa. 

The  underljnng  countr}-  rock  is  an  altered  Neocomian  [see 
Becker,  Mon.  XIII,  page  464],  crushed  and  altered  into  a 
material  which  is  found  through  the  entire  mine  in  various 
conditions  of  hardness.  Near  water  channels  it  is  a  dark- 
colored  clayey  material,  which  grades  into  a  light-gray  rock 
without  any  discernible  cleavage  or  fissility,  generally  rather 
soft,  occasionally  darker  colored,  very  hard  and  fine-grained. 
Its  position  near  the  eruptive  rocks,  and  comparisons  with  the 
silicified  shales  of  the  neighborhood  of  Mount  Konockti,  sug- 
gest that  the  shaly  country  rock  was  crushed  and  ground  by 
the  eruptive  actions,  and  its  original  stratification  destroyed. 
The  harder  portions  are  probably  the  result  of  contact  meta- 
morphism,  as  they  are  generally  found  in  contact  with,  or  close 
to,  the  igneous  rock.  This  material  is  locally  called  "mud- 
rock,"  and  is  found  also  in  other  mines.  It  was  found  in  the 
lower  level  of  the  Wide  Awake  shaft  (Sulphur  Creek),  and  in 
some  of  the  mines  in  San  Luis  Obispo  County.  On  the  con- 
tact of  the  "mudrock"  and  the  basalt  occurs  a  breccia,  gener- 
ally very  hard,  locally  called  "niggerhead,"  probably  fragments 
of  country  rock  recemented,  due  to  the  action  of  the  adjoin- 
ing basaltic  extrusions. 

Underground  explorations  have  proven  that  the  surface 
indications  in  many  instances  do  not  represent  underground 
conditions.  Sections  i,  2,  and  3  show  that  the  presence  of 
basalt  at  the  surface  does  not  indicate  an  igneous  dike  per- 
sistent in  depth.  The  section  of  shaft  No.  3  shows  basalt 
underlying  150  feet  of  breccia  and  "mudrock,"  while   levels  a 


NAPA    COUNTY.  83 

and  b  show  basalt  near  the  surface  and  none  in  the  under- 
lying territory.  The  section  over  pit  No.  3  (CC)  shows  how 
basalt  bowlders  and  tufa  have  spread  over  the  country  rock. 
It  would  require  systematic  underground  exploration  to  deter- 
mine the  exact  location  of  the  fissures  through  which  the  basalt 
extruded.  One  fact  is,  hov/ever,  beyond  doubt:  The  eruptive 
actions  are  intimately  connected  with  the  ore  deposition. 
Through  the  serpentine  runs  a  very  prominent  cropping  of 
opaline  material,  near  its  northeastern  boundary,  which  crop- 
ping is  almost  continuous  to  the  Boston  mine,  where  large  ore 
bodies  have  been  found  therein.  A  great  amount  of  explora- 
tion work  has  been  done  on  these  croppings  without  disclosing 
any  ore,  until  recently  a  seam  of  fair  ore,  from  6  to  12  inches 
wide,  has  been  discovered  therein,  about  400  feet  southeast  of 
the  furnace. 

All  the  territory  between  the  basalt  and  the  serpentine  shows 
the  action  of  mineral  springs,  which  have  formed  large  beds  of 
sinter  and  other  siliceous  material. 

Commencing  at  the  southeastern  part  of  the  property  are  the 
works  on  Soda  Hill.  The  underground  works  are  at  present 
inaccessible.  At  water  level  they  encountered  gas  and  water 
highly  charged  with  sodium,  arsenic,  etc. — salts.  The  opaline 
ledge  crops  here  ver\'  plainly  in  the  serpentine,  and  consider- 
able work  was  done  to  explore  it,  but  the  ledge  was  found  to 
be  absolutely  barren.  This  hill  is  surrounded  by  knolls  formed 
by  mineral  springs  now  dried  up.  The  surface  of  the  hill  is 
covered  by  tufa,  in  which  several  shallow  pockets  of  cinnabar 
were  found,  but  in  the  long  tunnel  (/;/)  [see  plan]  driven 
under  the  hill  no  ore  was  found.  The  formation  proved  to  be 
principally  breccia.  On  the  east  slope  of  the  hill  an  incline 
shaft,  25  feet  deep,  was  sunk  on  two  parallel  seams  of  black  ore. 

Northeast  of  Soda  Hill  (N.  50°  E.)  lies  pit  and  shaft  No.  3, 
the  most  extensive  works  on  the  property.  The  pit  is  in  the 
form  of  an  L.  The  north  and  south  leg  is  250  feet,  the  east 
and  west  leg  200  feet  long.  The  average  depth  is  about  100 
feet,  and  120  feet  at  its  deepest  point.  The  walls  of  the 
pit  are  partly  basalt,  more  or  less  leached,  partly  tuf?  and  de- 
composed breccia;  in  the  northwest  corner  the  "mudrock," 
exposed  at  Johntown,  appears.  The  bottom  of  the  pit  shows 
the  richest  in  the  northern  part,  but  cinnabar  ore  scams  are 
found  all  through  the  formation,  generally  vertical,  but  follow- 


84  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

ing  the  prominent  seams  in  the  rocks  in  ever}-  direction.  A 
number  of  tunnels  have  been  run  from  the  pit  into  the  adja- 
cent territory-,  especially  toward  the  basalt  to  the  east,  but  as 
the  pit  walls  are  nearly  vertical,  their  entrances  are  nearly  all 
inaccessible.  A  tunnel  {a)  [see  section  over  pit],  in  the  south- 
eastern part  of  the  pit,  about  25  feet  below  the  surface,  which 
is  accessible,  shows  first  decomposed  breccia,  partly  carrying 
some  ore,  partly  barren.  At  100  feet  from  the  mouth  solid 
basalt  comes  in.  On  the  contact  of  the  breccia  and  the  basalt 
lies  a  belt  of  opaline  rock,  largely  decomposed,  but  traversed 
by  hard  ribs  of  undecomposed  opaline,  accompanied  by  seams 
of  ore.  This  material  carries  some  lime.  The  same  section 
shows  that  at  a  lower  level  basalt  is  absent,  verticall}-  under 
its  occurrence  in  tunnel  a,  and  that  even  were  basalt  found  by 
driving  tunnel  l^  further,  this  could  hardly  belong  to  the  same 
body  as  that  found  in  a.  Shaft  No.  3  runs  into  basalt  at  a  depth 
of  150  feet  [see  section]  and  remains  in  that  formation  under- 
h-ing  "mudrock"  to  its  bottom  at  230  feet.  The  150-foot 
level,  from  which  tunnel  ^  is  run,  is  mainly  in  very  hard,  dark- 
colored  breccia.  At  this  level  metamorphic  sandstone  replaces 
the  breccia  and  persists  to  the  200-foot  level.  [See  sketch  of 
pit  Xo.  3.]  Below  the  150-foot  level  the  ore,  which  in  the 
breccia  is  scattered  in  seams  and  pockets  throughout  the  forma- 
tion, is  concentrated  in  a  contact  between  the  sandstone  and 
the  "mudrock,"  persisting  below  the  200-foot  level,  as  far  as 
yet  ascertained.  The  "mudrock"  appears  to  surround  the 
sandstone.  With  the  appearance  of  the  sandstone  is  intro- 
duced a  change  of  the  gangue  from  siliceous  to  calcareous, 
calcite  beginning  to  appear  in  the  veins,  while  the  waters  con- 
tain carbon  dioxide.  Here  then  the  replacement  of  silica  by 
carbon  dioxide  takes  place  below  a  zone  where  silica  predomi- 
nates. This  may  be  attributed  to  the  influence  of  basalt  on 
the  higher  horizon,  locally  heating  the  rocks  and  hence 
favoring  the  formation  of  silicates. 

Adjacent  and  to  the  northwest  of  pit  Xo.  3  lies  the  surface 
exposure  of  "mudrock"  at  Johntown.  This  exposure  does  not 
cover  over  two  acres.  The  original  discovery  of  cinnabar  was 
made  here,  but  all  the  works  are  almost  entirely  obliterated. 
Nearly  north  of  Johntown,  at  a  distance  of  about  600  feet,  is 
the  southeastern  end  of  a  row  of  pits  lying  in  a  northwesterly 
direction,  pretty  close  to  the  ridge  which  marks  probably  the 


NAPA    COUNTY.  85 

vent  of  the  basalt  extrusion.  These  pits  are  on  a  fissure  called 
the  Bunkhouse  vein.  The  ore  occurs  in  lenses  on  which  the 
pits  are  sunk,  the  intervening  spaces  being  nearly  barren. 
Occasionally  large  ore  chambers  are  found  in  the  ore  lenses.  The 
ore  forms  in  seams  in  the  "mudrock,"  but  prominentl}'  in  the 
tufJ  and  in  the  breccia,  and  occasionally  in  limestone  which  is, 
nearly  always,  only  found  in  connection  with  the  ore,  near  the 
surface  in  nodules.  In  this  connection  it  must  be  noted  that 
the  Knoxville  basalt  carries  a  high  percentage  (7.72%)  of  lime 
(CaO)  [see  Mon.  XIII,  page  159],  and  thus  the  lime  in  the 
ore  bodies  may  readih'  be  accounted  for.  Sections  i  and  2  give 
details  of  the  formation  as  exposed  in  the  pits  and  levels  run 
from  them.  The  development  tunnel  now  being  run  in  a  north- 
easterly direction  cuts  first  through  a  whitish  decomposed  tuff, 
then  successively  through  basalt,  breccia,  ledge  matter,  and 
"mudrock."  The  ledge  matter,  which  dips  away  from  the 
basalt,  is  a  fine-grained,  hard,  slightly  silicified  "mudrock,"  the 
cinnabar  forming  principalh'  on  its  contact  with  the  breccia. 

West  of  this  deposit,  near  the  serpentine,  is  a  large  deposit 
of  siliceous  material  (r),  prominently  chalcedony,  partly  of  a 
sintry  nature  formed  by  solfataric  springs,  the  remnants  of 
previous  igneous  action,  which  has  now  ceased  entirely.  The 
siliceous  material  is  mostly  in  somewhat  contorted  beds,  slightly 
resembling  the  chert  beds  of  the  Cretaceous,  dipping  southeast- 
erly and  having  a  varjang  thickness,  rather  inconsiderable. 
This  deposit,  locally  known  as  St.  Quentin,  is  about  400  feet 
long,  in  a  northwesterly  direction.  Some  isolated  small  knolls 
of  the  same  formation  are,  however,  found  farther  to  the  north- 
west. There  are  three  pits  on  this  deposit.  The  two  southerly 
pits  are  only  separated  by  a  wall  of  a  few  feet  wide  at  the  sur- 
face. The  third,  most  northerly,  is  .smaller  and  shallower.  A 
tunnel  {e)  has  been  run  under  this  pit  about  30  feet  below  the 
surface  in  a  breccia  formed  of  fragments  of  various  rocks 
cemented  by  silica.  At  the  breast  some  chalcedony  is  found. 
The  cinnabar  occurs  generally  in  the  seams  of  the  siliceous 
beds,  often  mixed  with  sand,  so  that  it  can  be  removed  with 
scrapers  out  of  the  seams.  In  the  eastern  part  of  the  deposit 
the  siliceous  material  is  impregnated  throughout  with  the 
cinnabar  in  a  microcrystalline  condition,  indicating  a  contem- 
poraneous deposition  of  the  cinnabar  and  the  silica.  No 
macroscopical  crystals  of  cinnabar  are  found  anywhere  in  this 


86  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

deposit.  The  ore  has  not  been  found  to  persist  in  depth  in  any 
of  the  three  pits. 

To  the  north  of  the  St.  Quentin  lies  the  basalt  shaft  and  pit. 
The  vertical  shaft  lies  north  of  the  pit.  At  a  depth  of  130 
feet,  the  lower  level  was  run  from  the  shaft  under  the  pit, 
which  is  about  400  feet  long  in  a  north  and  south  direction. 
Both  shaft  and  pit  start  in  basalt.  At  130  feet  "mudrock" 
came  in  the  shaft  from  the  west.  The  territory  under  the  pit 
is  also  reached  by  a  long  tunnel  (//),  with  a  shaft  at  the  end, 
20  feet  in  depth,  which  communicates  with  a  large  chamber  40 
feet  wide,  45  feet  high,  and  80  feet  long  in  the  bottom,  situated 
under  the  pit,  entirely  excavated,  having  contained  a  large 
body  of  good  ore.  The  ledge  on  which  the  pit  is  located  has  a 
north  and  south  strike,  varying  from  that  of  the  other  deposits. 
It  is  entirely  inclosed  in  basalt,  and  in  depth  abuts  abruptly 
against  a  stratum  of  hard  sandstone,  dipping  slightly  east, 
from  2  to  6  feet  thick;  the  ore  only  occasionally  penetrating 
slightly  into  seams  of  this  stratum,  which  is  underlaid  by 
"mudrock."  This  body  of  basalt,  no  feet  high,  is  hence  only 
a  surface  flow,  which  is  confirmed  by  {d)  and  (/).  [See 
below.]  The  ore  bodies  in  the  basalt  were  so  profitable  that 
extensive  explorations  were  made  in  the  "mudrock"  to  find 
their  continuation  in  depth,  but  without  result;  hence  the  con- 
clusion that  the  ore  deposition  is  intimately  connected  with 
the  basalt,  and  that  the  hard  stratum  overlying  the  "mudrock" 
prevented  the  solutions  from  entering  therein,  acting  as  an 
impervdous  stratum.  The  ledge  matter  is  throughout  asso- 
ciated with  calcite.  [See  above,  Bunkhouse  vein.]  The  ledge 
pinched  materially  about  50  feet  from  the  surface;  at  this 
horizon  the  vein  filling  is  limestone,  containing  narrow  seams 
of  cinnabar.  In  the  lower  part  it  consists  of  very  profitable 
ore  seams  interstratified  with  seams  of  limestone  about  a  foot 
wide.  In  the  northern  end  of  the  deposit  "mudrock"  is  more 
prominent. 

A  couple  of  hundred  feet  northwest  of  the  basalt  shaft 
another  north  and  south  vein  {b)  has  been  worked  in  a 
weathered  basalt  from  i  to  4  feet  wide,  and  from  150  to  200 
feet  long.  To  a  depth  of  50  feet  this  vein  was  in  places  very 
rich.  At  that  depth,  however,  the  rock  suddenly  hardened  and 
simultaneous!}'  the  vein  became  poorer,  and  had  to  be  aban- 
doned at  a  depth  of  60  feet. 


NAPA   COUNTY. 


87 


To  the  southwest  of  the  basalt  pit,  between  this  pit  and  pit 
No.  3  of  St.  Quentin,  a  shaft  {d)  has  been  sunk  to  the  under- 
lying "mudrock"  which  was  also  found  in  a  pit  (/"i)  west  of 
the  basalt  pit. 

Extensive  works  (/.,)  west  of  the  basalt  pit  and  northwest 
of  St.  Quentin,  near  the  serpentine,  consist  of  a  large  open  cut, 
tunnels,  and  stopes,  showing  that  large  bodies  of  ore  have  been 
taken  out  of  this  ground.  The  formation  is  leached  igneous 
rocks,  chalcedony  seams,  and  brecciated  sandstones.  Two 
drifts  have  been  run  toward  these  works.  The  upper  tunnel, 
75  feet  below  the  surface  at  the  open  cut,  cuts  through  silica 
concretions,  then  leached  basalt,  basalt,  and  on  the  contact  of 
the  basalt  with  an  altered  sandstone  a  vein  dipping  southwest, 
which,  judging 
from  the  old 
stopes,  contain- 
ed a  number  of 
ore  bodies  of 
lenticular  form. 
The  lower  tun- 
nel, 140  feet  be- 
low the  same 
surface,      runs 

mainly  in  serpentine  material;  at  300  feet  it  cuts  across  a  vein 
having  a  nearly  east  and  west  strike;  an  understope,  20  feet 
deep  and  70  feet  long,  shows  that  the  ore  body  lies  in  hardened 
contact  "mudrock."  A  shaft  80  feet  deep  shows  that  the 
basalt  lies  here  north  of  the  "mudrock,"  while  in  the  upper 
tunnel  it  lies  south  thereof.  The  stope  [see  cross-section, 
Fig.  28]  showed  good  ore,  metacinnabarite,  and  some  native 
mercury  in  pockets  next  to  the  basalt.  When  the  stope 
reached  the  understoping  in  the  lower  tunnel,  it  was  shown 
that  the  lower  vein  had  a  cross  strike  to  that  on  which  the 
vein  understoping  was  done,  and  the  latter  was  never  found 
below. 

At  the  northwest  end  of  the  property  is  the  knoll  of  which 
section  3  gives  a  cross-section.  Several  small  pockets  of  ore 
were  found  in  the  tufa  overlying  the  top.  The  tunnel  (/) 
cuts  through  the  entire  knoll,  running  for  the  greatest  part  in 
serpentine.  Ore  was  only  found  in  the  basalt  near  the 
northern  end.     It  forms  in  seams  in  the  basalt.     In  some  of 


Fig.  28.    Manhattan  Mine— Section  over  the  works  at  (/,). 


88  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

these  seams  the  main  filling  is  formed  by  bands  of  iron  pyrite, 
with  thin,  intercalated  seams  of  cinnabar;  in  others  the  filling 
is  opaline  silica.  The  ore  in  the  surface  pockets  carried  also 
considerable  iron  pyrite.  The  hill  is  mainly  serpentine  and 
shale;  the  absence  of  basalt  in  the  lower  tunnel  may  be  caused 
by  a  fault,  the  upper  part  of  the  basalt  having  slid  northeast 
with  the  slope  of  the  hill. 

While  the  mine  is  not  a  great  producer,  it  .s  of  great  geologi- 
cal interest,  because  the  relations  between  the  igneous  rocks, 
the  countT}'  rock,  and  the  ore  deposits  can  be  so  well  traced. 
The  absence  of  ore  deposits  in  the  serpentine,  even  where  it  is 
contiguous  to  the  igneous  rocks,  must  be  noted.  In  opposition 
to  the  ore  occurrence  in  the  Oathill  mine,  the  ore  deposits  are 
all  contiguous  to  the  basalt  and  do  not  extend  to  an}-  distance 
from  it,  except  in  the  St.  Quentin  deposit,  where  the  cinnabar 
has  been  deposited  from  solfataric  waters,  which  must  have 
been  related  to  the  basalt.  Again,  in  the  ^tna  mine  the  pre- 
vailing conditions  indicate  that  the  cinnabar  was  disseminated 
through  the  sandstone,  and  formed  into  workable  ore  bodies  by 
secondary  concentration  in  some  way  connected  with  the  ser- 
pentine and  basalt,  while  in  this  mine  all  indications  tend  to 
the  conclusion  that  the  igneous  rocks  are  the  direct  source 
of  the  cinnabar.  In  the  neighboring  Boston  mine  there  are 
reasons  to  suppose  a  course  of  ore  formation  similar  to  that  in 
the  ^tna  mine.  Considering  that  the  Boston  and  Manhattan 
deposits  are  only  one  mile  interdistant,  and  that  from  the 
topograph}'  it  might  be  inferred  that  while  not  appearing  at 
the  surface,  the  vent  through  which  the  basalt  extruded  in  the 
Manhattan  persists  toward  the  Boston,  the  entirely  diSerent 
nature  of  ore  formation  in  these  two  mines  is  very  noteworthy. 

It  is  to  be  regretted  that  in  no  place  in  the  Manhattan  mine 
has  the  commercial  development  of  the  ore  deposits  caused  the 
underground  works  to  be  run  in  a  manner  to  determine  the 
vent  of  the  basalt  extrusion,  or  whether  on  or  near  this  vent 
deposits  of  greater  persistence  in  depth  would  be  found.  The 
fact  that  every  deposit  as  yet  opened  in  this  mine  terminates 
in  depth  with  the  basalt,  justifies  the  expectation  that  such 
persistence  might  be  the  case. 

The  irregular  basalt  occurrences  found  in  the  mine  are  prob- 
ably intrusions,  which  follow  pre-existing  fissures,  joints,  bed- 
ding planes,  or  contacts,  which  would  account  for  the  lack  of 


NAPA    COUNTY. 


89 


heat  effect  on  the  adjoining  rocks  by  these  igneous  intrusives. 
[See  N.  S.  Shafer,  Bulletin  Geological  Society  of  America, 
vol.  X,  page  253.] 

South  of  the  furnace  in  the  serpentine  is  an  exposure  of 
breccia  covering  a  couple  of  acres,  which  is  used  as  building- 
stone. 

The  mine  is  equipped  with  one  coarse-ore  and  one  fine-ore 
Knox  &  Osborne  furnace,  both  of  24  tons  capacity.  The 
coarse-ore  furnace  is  only  used  for  about  two  months  in  the 
year,  the  great  majorit}'^  of  the  ore  as  it  comes  from  the  mine 
being  proper  material  for  the  fine-ore  furnace. 

J3  a  ■!,  o-/  t   c  0  7-e  , 


< 


Fig.  29.     Xapa  Consolidated  Miues.     [See  page  91.] 


Oathill  Mine  (or  Napa  Consolidated  Quicksilver  Mines). — 
Mayacmas  District.  In  Sees.  27,  28,  33,  and  34,  T.  10  N., 
R.  6  W.  The  Napa  Consolidated  Mining  Company,  of  Boston, 
Mass.,  owner ;  B.  M.  Newcomb,  Oathill,  Napa  County,  super- 
intendent. [See  Mon.  XIII,  U.  S.  G.  S.,  page  355  ;  Report 
State  Mining  Bureau  of  Cal.,  XI,  pages  65-72  ;  XII,  page  364 ; 
XIII,  page  598.]  This  property  covers  a  large  area  of  ground 
between  James  Creek  and  Bucksnorter  Creek.  It  has  been  for 
years  since  its  opening  in  1876,  and  is  still,  one  of  the  largest 
producers  in  the  State. 

The  cinnabar  deposits  in  these  mines  lie  entirely  in  a  belt  of 


NAPA    COUNTY. 


91 


sandstones,  which  abut  and  surround  a  core  of  basalt.  The 
sandstones  occur  in  thin  beds,  with  partings  filled  with  attrition 
products  and  clay.  The  stratification  and  also  the  mineralized 
zone  have  a  general  tendency  toward  parallelism  to  this  core. 
[See  van  Hise,  i6th  Ann.  Report,  U.  S.  G.  S.,  Part  I,  page  637.] 
Nearing  this  core  the  stratification  becomes  more  irregular  and 
contorted.  The  veins,  practically  fissure  fillings  in  the  sand- 
stone country  rock,  are  from  a  few  inches  to  a  few  feet  wide. 
Their  general  plan  is  given  in  Fig.  29.  They  are  in  their  strike 
independent  of  the  bedding  planes,  and  carry  generallj^  a  clay 
gouge  on  the  foot  wall.  In  places  chambers  have  been  formed 
in  the  walls  of  the  fissures,  on  that  side  of  the  vein  where  the 
sandstone  was  not  protected  by  a  clay  gouge  from  the  action  of 
the  percolating  solutions. 

A  peculiar  phenomenon 
occurs  at  the  crossing  of 
the  Humboldt  and  Osceola 
veins.  In  both  veins  near 
the  crossing  shoots  of  good 
ore,  about  500  feet  long, 
were  found.  The  Hum- 
boldt vein,  which  is  more 
of  a  conglomerate  nature 
than  any  of  the  other  veins, 
persists  on  both  sides  of 
the  crossing ;  but  the  Os- 
ceola is  hardly  discernible 

at  the  crossing  point  and  makes  only  at  a  certain  distance  on 
both  sides  of  the  crossing  point.      [See  Fig.  30.] 

The  secondar}^  concentration  of  the  workable  ore  bodies  in 
this  group  of  mines  must  probably  be  attributed  to  the  contact- 
metamorphic  action  of  the  basalt  core.  It  is,  however,  a  note- 
worthy fact  that  here  the  ore  bodies  do  not  persist  to  the  basalt 
core.  The  explanation  may  be  that  the  heat  and  pressure  due 
to  the  intrusion  of  this  large  body  of  basalt  raised  the  temper- 
ature so  high  in  the  close  neighborhood  of  its  intrusion  that 
the  mercury  was  carried  off  in  vapor  form  and  deposited  in  a 
region  where  the  temperature  and  pressure  were  lower.  The 
mine  is  equipped  with  two  50-ton  Scott  furnaces,  one  of  which 
was  rebuilt  in  1902  after  sixteen  years  of  service. 


Fig.  30. 


Xapa  Consolidated   Mines— Crossing 
of  two  veins. 


92  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

Philadelphia  Mine. — Mayacmas  District.  In  Sec.  26.  T.  10  X., 
R.  6  \V.  Owner.  M.  Pluth,  of  Oathill,  Napa  County.  The 
mine  is  located  in  the  southeastern  end  of  the  divide  between 
James  Creek  and  Pope  Valley,  running  down  from  the  Oathill 
divide.  The  belt  of  serpentine  running  northwest  from  ,Stna 
Springs  along  the  southwest  ridge  of  Pope  Valley,  crossing 
James  Creek,  near  its  mouth,  follows  the  divide  for  some 
distance,  and  some  promising  float  is  found  on  top  of  the  ridge. 
A  crosscut  tunnel  270  feet  below  the  ridge  has  not  yet  reached 
the  ledge;  its  breast  is  in  basalt,  indicating  an  igneous  core  in 
this  divide. 

Red  Elephant  and  Northern  Light  Mines. — Knoxville  District.  I  n 
Sec.  3,  T.  II  N.,  R.  5  \V.  The  former  mine  is  owned  by  \V.  G. 
Tremper,  of  Lower  Lake,  Lake  County.  The  latter  mine, 
south  of  the  Red  Elephant,  is  owned  by  Fr.  Josh,  of  Lower 
Lake,  Lake  County.  In  the  Red  Elephant,  a  little  surface 
cinnabar  has  been  found,  but  none  of  a  number  of  shallow 
cuts  and  pits  show  any  cinnabar  ore  in  place. 

Summit  Mine.— In  Sec.  19,  T.  7  X.,  R.  5  W.  S.  W.  Keeney, 
Xo.  563  Parrott  Building.  San  Francisco,  owner. 

Twin  Peaks  Mine. — Mayacmas  District.  In  Sec.  4,  T.  9  X.. 
R.  6  W.,  and  Sec.  33.  T.  10  X.,  R.  6  W.  Owners,  B.  A. 
Wilson,  F.  Smyth,  and  H.  Herrick,  of  Middletown,  and  J. 
Hayes,  of  Harbin  Springs,  Lake  Count}*;  B.  A.  Wilson,  super- 
intendent, Oathill,  Xapa  County.  This  mine  can  only  as 
yet  be  considered  as  a  prospect;  it  has,  however,  some  good 
ore,  which  is  reduced  in  a  small  retort  furnace.  The  cinnabar 
ore  is  formed  in  the  cracks  and  fissures  of  the  opaline  rock, 
and  is  accompanied  by  a  sensible  amount  of  iron  sulphides. 
The  ore  body  lies  rather  flat,  and  has  a  strike  nearly  north 
and  south,  dipping  about  30°  to  the  west.  Above  the  ore  lies 
a  layer  of  grayish-green  talc  (probably  decomposed  serpentine), 
which  shows  cinnabar  all  through  it;  above  which  lies  a  black 
gouge,  which  in  places  shows  clearlj'  the  structural  forms  of 
the  original  opaline  rock.  The  formation  in  this  mine,  which 
lies  close  to  the  igneous  bodies,  is  very  much  distorted;  but 
when  found  in  place,  the  ore  bodies  will  probablj'  be  found  on 
the  same  contact  of  serpentine  and  sandstone  as  the  neighbor- 
ing Corona  mine.  The  property  is  equipped  with  a  lo-pipe 
retort,  and  the  ore  must  have  been  of  a  good  grade,  as  the 
monthly  product  is  reported  to  be  40  flasks. 


SOLANO    COUNTY. 


93 


SOLANO  COUNTY. 

St.  John  Mine.— In  Sec.  33,  T.  4  N.,  R.  3  W.  The  St.  John's 
Consolidated  Quicksilver  Mining  Company,  owner;  Ch.  Bone, 
president;  J.  H.  Sayre,  secretary,  room  5,  No.  405  Montgomery 
street,  San  Francisco;  A.  A.  Tregidgo,  superintendent,  Vallejo, 
Solano  County.  This  mine  was  opened  in  1873  and  was  oper- 
ated until  1880,  during  which  time  it  produced  11,530  flasks. 
\\'ork  was  then  abandoned  until  1S99,  when  the  present  com- 
pany resumed  by  reopening  some  of  the  old  works. 

A1-^\-    /,  o    I 1 1  200 


€fyv,'^";,... 


-s^.. 


w. , 


■•■/■I 
■/ 


■^•iW.. ... 


—  6, 


.•-  e  ■  - 


Fig.  31.     St.  John  Mine— Section  east  and  west  over  main  tunnel  shaft. 

The  mine  is  located  in  a  basin  between  Mount  Luffman  to 
the  west  and  Mount  St.  John  to  the  east.  These  mountains 
are  characterized  by  the  bold  outcrops  of  two  bodies  of  meta- 
morphic  sandstones.  Nearh^  the  entire  inter\-ening  surface  is 
covered  by  sandstone  debris,  but  all  the  dumps  of  the  old 
tunnels  show  schist,  and  in  some  of  the  larger  cuts  the  contact 
of  the  .schists  and  sandstones  can  be  found.  The  sandstones 
especially  those  of  the  Mount  St.  John  ridge,  show  a  prominent 
north  and  south  fracture  system.  The  schists  probabh-  lie  in 
a  trough,  having  a  general  northern  trend  in  the  sandstone 


1 

1 

^HH 

I^^H 

Hl^^''^                       ^^^1 

wSi 

0 

1^^ 

^"■""^^=          *^^l 

J^M 

i^riH'   ^^1 

n 

^^^^^K.^ 

Hi 

^^^^^^^^^^^^^^       ''".^^^^■1 

^1 

K' 

J  • .    "'  I^^^B 

■ 

^^fcigv  .'^- .-^.^^icrr  ', 

1,"    ^j'-'.'^.    .;  "T 

PHOTO  No.  8.     ST.  JOHN  MINE  AND  FURNACE. 


PHOTO  No.  'J.     ST.  JOHN  QUICKSILVER  MINE. 


SOLAXO    COUNTY.  95 

formation ;  but  whether  the  latter  formation  underlies  the  entire 
territory  has  not  as  yet  been  determined.  Fig.  31  shows  that 
below  the  level  of  the  main  tunnel  another  body  of  schists  lies 
in  the  sandstone.  The  contact  of  the  sandstones  and  the 
schists  is  ver>'  irregular  and  intricate.  The  schists  appear  to 
carry  some  magnesia,  at  least  sulphate  of  magnesia  forms 
in  the  main  tunnel  in  a  couple  of  places.  The  ore  croppings 
are  found  at,  or  in  close  proximity  to,  the  ridges  of  sand- 
stone. There  are  a  great  amount  of  open  cuts,  drifts,  and 
shallow  shafts  on  these  croppings.  The  principal  work,  how- 
ever, was  done  in  the  main  tunnel,  through  which  two  distinct 
ore  bodies— the  main  tunnel  ore  shoot  and  the  San  Miguel 
ore  shoot — have  been  worked.  The  former  was  cut  by  the 
main  tunnel  at  a  depth  of  250  feet  below  the  surface,  and  a 
shaft  sunk  on  it  from  that  level  to  a  depth  of  180  feet.  The 
San  Miguel  ore  shoot  was  reached  by  a  crosscut  about  100 
feet  long,  at  the  end  of  which  a  shaft  180  feet  deep  was  sunk, 
all  in  sandstones.  The  latter  works  are  at  present  inaccessible. 
The  main  tunnel,  course  nearly  north,  which  has  been  retim- 
bered,  reaches  the  old  stopes  at  11 20  feet  from  the  entrance. 
It  runs  through  schists,  near  the  entrance  thinly  bedded,  con- 
torted, in  places  showing  slickensides,  and  becoming  more 
massive  in  depth.  This  material  resembles  very  closely  the 
"mudrock"  in  the  Manhattan  mine.  At  700  feet  from  the 
mouth  the  tunnel  intersects  a  sandstone  dike,  about  6  feet 
wide,  course  N.  60°  E. 

The  metamorphic  sandstone  is  in  places  altered  to  quartzite, 
and  in  other  places  is  somewhat  porphyritic.  It  shows  zones 
of  fractures,  nearly  parallel  with  the  contact,  not  over  one  to 
one  and  a  half  inches  interdistant.  These  are  sometimes  cut 
off  by  a  set  of  more  irregular  cross  fractures,  causing  the  rock 
to  break  very  irregularly,  sometimes  conchoidal.  The  ore 
forms  principally  in  the  zones  of  parallel  fracturing  and  adjoin- 
ing thereto.  Where  the  fissuring  allowed  it,  the  cinnabar  was 
deposited  with  a  quartzose  gangue.  Often  it  forms  face  metal 
on  the  fissure  walls,  which  show  signs  of  movements  after  the 
deposition.  Where  the  rock  is  more  compact,  small  aggregates 
of  minute  cinnabar  crystals  are  disseminated  through  the  rock, 
generally  associated  with  iron  pyrite.  The  mineralization  was 
contemporaneous   with,    or   anterior   to,    this   metamorphism. 


96 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


200 

_J 


/■£■£"  r 


Possibl}-  the  cinnabar  was 
originally  diffused  through 
the  sandstone  and  leached 
//.  out  and  concentrated  during 
^  the  metamorphism  of  the 
sandstone.  At  and  below  the 
level  of  the  main  tunnel  the 
ore  forms  exclusivel}'  in  the 
sandstone,  but  nearer  the  sur- 
face it  is  found  in  the  schists. 
At  the  point  of  intersection 
with  the  main  tunnel  ore 
shoot,  the  main  tunnel  makes 
an  offshoot  to  the  west  to 
avoid  the  old  works  [see  Fig. 
32],  and  continues  then  in  a 
northeasterly  direction  ( N. 
20°  E.).  It  passes  first  through 
sandstone,  and  then  follows 
the  northeastern  contact  be- 
tween the  sandstone  and  the 
schists.  Xo  ore  has  as  yet 
been     found     in     this     drift. 

Judging  from  the  old  stopes  the  ore  body  at  the  level  of  the 

main    tunnel     was  |si 

about  70  feet  long 

and  from  15  to  25 

feet  wide.      Below 

this   level  two  ore 

bodies  were  worked  ^■^'^ -z-'^ 

from    the    shaft — 

one  west,  the  other 

east  and  southeast 

of  the  shaft — sep- 
arated by  about  60 

feet      of     barren 

ground.    The  stope 

on    the    ore    body 

west  goes  down  to 

the   130-foot  level, 

where    it    forms   a 


Fig.  32.     St.  John  Mine — Plan  showing 
main  luiinel  west  of  shaft. 


^  Ore    /30    /ei^e/ 
•IllUk  "      /80'      " 


Fig.  33.     St.  John  Mine — Plan  of  works  in  main 
tunnel  shaft. 


SONOMA    COUNTY.  97 

bod}-  about  60  feet  long  and  from  6  to  8  feet  wide,  having 
a  course  of  about  N.  10°  W.,  starting  about  30  feet  from 
the  shaft.  [See  Fig.  33.]  The  ore  body  east  of  the  shaft 
on  this  level  is  larger  and  more  irregular.  In  the  180- foot 
level  the  contact  of  the  sandstone  and  schists  east  of  the  shaft 
runs  about  N.  50°  W.  In  the  sandstone  are  found  three  zones 
of  cinnabar  deposition  running  about  parallel  to  the  contact, 
going  from  the  latter  southeast,  respectively,  one  inch  or  less, 
^y^,  and  4  feet  wide.  The  sandstone  has  not  been  cut  through 
by  the  crosscut,  54  feet  long,  from  the  northeast  contact.  The 
stope  is  about  40  feet  long  on  the  strike.  The  shaft  has  lately 
been  sunk  50  feet  deeper.  In  the  230-foot  level  the  course  of 
the  same  contact  is  about  north,  but  the  works  have  not  as  yet 
exposed  any  ore.  The  mine  is  equipped  with  two  coarse-ore 
shaft  furnaces  of  the  John  Neat  patent.  For  a  detailed  descrip- 
tion of  the  plant,  see  the  chapter  on  Metallurgy. 

SONOMA  COUNTY, 

Almaden,  Incandescent,  and  Tunnel  Site  Group. — Mayacmas  Dis- 
trict. C.  C.  Thomas  and  E.  Grimmer,  owners.  Pine  Flat, 
Sonoma  County.  In  Sees.  31  and  32,  T.  11  N.,  R.  8  W. 
Includes  the  Almaden,  Incandescent,  and  Tunnel  Site  claims. 
To  the  northeast  of  the  Eureka  mine.     No  development. 

Bacon  Consolidated  Group. — Mayacmas  District.  Includes  the 
Edith,  Maud,  St.  George,  Golden  Gate,  and  Eagle  mines,  in 
Sees.  II  and  12,  T.  10  N.,  R.  8  W.  B.  Getleson,  owner,  Mid- 
dletown,  Lake  County.     Idle. 

Boston  Group. — Mayacmas  District.  Wm.  F.  OXeary,  A.  C. 
Huebner,  and  J.  Conran,  owners,  Healdsburg,  Sonoma  County. 
This  group  consists  of  three  claims — the  Boston,  Earlene,  and 
Hope — in  Sees.  3,  9,  and  10,  T.  10  N.,  R.  8  W.  Two  short  tun- 
nels are  run  on  this  property.  The  upper  tunnel,  very  close  to 
the  crest  of  the  ridge,  course  N.  63°  W.,  is  100  feet  long;  at  the 
breast  a  drift  of  about  25  feet  long,  on  a  course  about  north,  is 
run  on  the  vein ;  a  thin  seam  dipping  about  30°  to  the  north  runs 
parallel  with  this  drift  and  carried  some  cinnabar.  The  lower 
tunnel,  75  feet  below  the  upper,  runs  on  the  same  course  320 
feet;  it  cuts,  at  230  feet  from  the  entrance,  a  vein  having  a 
7— yK 


98  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

nearly  north  and  south  course.  The  hanging  wall  is  too 
decomposed  to  state  the  character  of  the  rock;  the  foot  wall  is 
sandstone.  The  vein  filling  is  opaline  rock,  with  a  bedding 
across  the  vein.  In  the  north  crosscut,  25  feet  long,  the  vein 
narrows  at  the  breast;  in  the  south  crosscut,  10  feet  long,  some 
ore  was  found  near  the  main  tunnel,  but  at  the  breast  no 
cinnabar  was  found. 

Gnnabar  King  Group. — Mayacmas  District.  Cinnabar  Mining 
Company, owner;  E.S.Rowland, secretary,  Healdsburg, Sonoma 
County.  The  group  includes  the  Cinnabar  King,  Champion, 
Pa3-master,  Goodenough,  and  Helen  claims,  and  two  millsites  on 
the  southwestern  slope  of  Pine  Mountain,  in  Sec.  11,  T.  10  X., 
R.  8  W.  [See  repoirts  State  Mining  Bureau  of  Cal.,  XI,  page 
461 ;  XII,  page  371 ;  XIII,  page  602.]  This  propertj-  is  the  only 
one  on  the  west  slope  of  Pine  Mountain  on  which  some  work 
has  been  done  lateh-.  The  general  course  of  the  croppings  is 
northwest.  Several  open  cuts  show  some  ore  on  the  dumps. 
This  ore  forms  in  silicified  serpentine,  in  seams  parallel  to  the 
strike.  The  dip  of  the  ledge  is  southwesterly.  There  is  on 
the  propert}'  a  shaft  55  feet  deep,  on  a  ven,-  flat  incline;  a  lower 
tunnel,  660  feet  long,  at  a  level  200  feet  below  the  collar  of  the 
shaft;  and  an  upper  tunnel  87  feet  below  same  collar.  These 
works  are  inaccessible, 

Cloverdak  Mine. — Maj-acmas  District.  In  Sees.  3, 4,  9,  and  10, 
T.  1 1  X.,  R.  9  W.  This  includes  the  Cloverdale,  Sunrise,  and 
Mount  Vernon  groups,  the  Mercun.-  and  Manzanita  claims,  and 
some  inclosing  lands,  on  both  sides  of  Big  Sulphur  Creek, 
near  the  mouth  of  Squaw  Creek.  Owners,  H.  B.  and  C.  A. 
Lawley,  The  Geysers,  Sonoma  County.  [See  Mon.  XIII,  U.S. 
G.  S.,  page  376;  Report  State  Mining  Bureau  of  Cal.,  XIII, 
page  603.]  This  mine  was  opened  in  1S72,  the  furnace  being 
constructed  in  1S75,  and  run  for  twenty-six  months,  producing 
about  3200  flasks  of  mercurj'.  The  works  were  closed  down 
in  1878.  Work  was  resumed  in  1898  b}-  the  present  owners, 
who  started  the  furnace  in  Xovember,  1S99.  The  latter  has 
run  steadily  for  the  last  eighteen  months,  producing  about  720 
flasks.  At  the  end  of  1902  it  was  producing  about  50  flasks 
per  month.  The  mine  workings  consist,  besides  several  large 
open  cuts,  of  about  1500  feet  of  drifts  and  150  feet  of  shafts. 
On  the  Mount  Vernon  group  very  little  development  has  been 


SONOMA    COUNTY.  99 

done.  A  body  of  thinly-bedded  cherty  rock  between  sand- 
stone walls  has  been  opened  up  in  the  Mount  Vernon  claim  by 
a  shaft  and  two  tunnels.  The  latter,  which  are  almost  vertically 
above  each  other  [see  Fig.  34] ,  show  some  face  cinnabar  on  the 
fissure  planes  of  the  chert.  The  strike  of  this  body  of  stratified 
chert  is  about  northeast,  the  dip  very  irregular  about  southeast. 
In  the  upper  tunnel  the  seams  between  the  chert  beds  carry 
sulphur,  the  only  similar  occurrence  seen  on  the  property. 

The  property  is  traversed  by  several  nearly  parallel  ledges  of 
thinly-stratified  chert,  inclosed  by  sandstone.  These  ledges 
have  generally  a  northwest  strike  and  northeast  dip.  The 
thickness  of  the  chert  beds  varies  from  a  half  to  three  inches; 
that  of  the  clay  seams  from  a  knife  blade  to  quarter  of  an  inch, 
except  in  one  place,  in  the  Murphy  tunnel  or  No.  4  ledge, 
where  chert  and  clay 
seams  are  for  some  dis- 
tance much  thicker.     In 

places,    both   the    chert  d//9<yo)^^ 

and     clay    are     colored 
light  green  by  silicate  of 
iron.     In  the  same  tun-  sf/9/0/^ 
nel     the     thick     gouge 
above  the  chert  consists  >0£.e''£ , 

e  ,.  .     ,  Fig.  34.    Cloverdale  Mine— Section  overworks, 

for  some  distance  of  de-  j^^„„t  vemou  claim. 

composed  sandstone  and 

clay  interbedded  like  the  chert  formation.  No  serpentine  is 
found  on  the  property — the  country  rock  being  all  sandstone; 
but  on  the  ridge  of  the  divide  between  Squaw  Creek  and  Big 
Sulphur  Creek,  above  the  mine,  some  porphyritic  and  dioritic 
rocks  are  found,  cutting  through  the  sandstone  which  forms 
the  backbone  of  the  ridge.  The  chert  shows  very  plainly  on  the 
lower  part  of  above-mentioned  dividing  ridge,  which  has  there 
a  general  direction  nearly  east  and  west,  and  is  cut  at  an 
obtuse  angle  by  those  ledges. 

Starting  up  the  ridge  from  the  furnace,  the  first  ledge,  No.  i , 
about  25  feet  wide,  is  barren  at  the  ridge,  but  to  the  southeast, 
in  the  Glory  Hole  tunnel,  shows  very  good  ore. 

On  the  next  ledge.  No.  2,  the  former  company  twenty  years 
ago  mainly  concentrated  its  work,  producing  3100  fiasks  from 
it.  The  ledge  was  worked  both  by  open  cut  and  in  the  Cat- 
sin's  tunnel.     At  present  this  ledge  is  worked  on  the  south 


SONOMA    COUNTY. 


101 


slope  of  the  ridge  by  three  open  cuts,  forming  a  nearly  continu- 
ous line  of  workings  [see  photograph  Fig.  35,  Ki,  K.,  and  K3J ; 
the  open  cut  at  the  top  of  the  ridge  (Ki)  is  60  feet  high  and 
48  feet  wide,  and  furnishes  at  present,  practically  without  sort- 
ing, all  the  ore  run  during  the  summer  season  through  the 
furnace,  which  has  a  capacity  of  7  tons  of  ore  per  day  and 
produces  from  45  to  50  flasks  per  month.  The  more  compact 
and  regularly  bedded  part  of  the  ledge  carries  the  metal  mostly 
as  face  metal  and  incrustations  in  the  fissures;  the  crushed 
portions  are  much  richer  and  carry  the  metal  more  in  seams 
and  bunches. 


/i//3 


S  <k  tt   £/  »  f 


Fig.  36.     Cloverdale  Mine — Plan  and  section  of  Murphy  tunnel. 

The  next  ledge.  No.  3,  is  only  separated  from  Xo.  2  b}'  a 
narrow  belt  of  sandstone,  and  has  been  extensively  worked  by 
open  cut  in  the  Old  Ray  workings  on  the  north  slope.  It 
shows  onl}'^  slightly  on  the  south  slope  of  the  ridge,  principally 
in  the  mouth  of  the  Murphy  tunnel.      [6,  Fig.  35.] 

Ledge  No.  4,  or  Murphy  ledge,  shows  principally  in  the 
Murphy  tunnel.  It  is  about  25  feet  wide.  [See  Fig.  36.]  The 
chert  beds  are  mostly  from  one  to  three  inches  wide,  the  gray 
clay  seams  one  quarter  to  one  inch  ;  cinnabar  ore  making  prin- 
cipally on  the  faces,  richer  nearer  the  hanging  wall,  which  is 
peculiarly  interstratified,  as  above  mentioned,  with  clay  seams 
like  the  chert  beds.     These  chert  beds,  wherein  the  cinnabar 


102  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

ore  makes,  are  ven,-  similar  to  the  ledge  matter  of  the  Great 
Western. 

The  company  has  a  small  incline  furnace  of  7  tons  capacity 
per  day,  and  a  lo-pipe  retort  furnace. 

Qyde  Mine. — Mayacmas  District.  G.  Hemmingwaj-  and  F. 
Baumeister,  owners,  The  Geysers,  Sonoma  County.  In  Sec.  24, 
T.  10  X.,  R.  8  W.,  on  the  north  fork  of  Little  Sulphur  Creek 
(Devil's  Den  Canon).  This  mine  is  close  to  and  partially 
surrounded  by  the  Culver- Baer  property,  and  is  located  on 
the  same  ledge  of  croppings  as  the  Old  Oakland  (Lost  Ledge 
and  Geyser)  group  of  that  property.  The  croppings  show 
very  boldly  on  the  northeast  bank  of  the  creek,  and  the  latter 
is  full  of  large  ore  bowlders.  The  old  works  are  inaccessible, 
but  on  the  dumps  several  tons  of  ore  of  a  good  quality  are 
found. 

Crown  Point  (Sonoma)  Mine.— Mayacmas  District.  The  Crown 
Point  Quicksilver  Mining  Company,  owner;  S.  S.  Bogle,  secre- 
tary', Santa  Rosa,  Sonoma  Count}'.  It  includes  the  Sonoma 
Xos.  3  and  4,  Hercules,  and  Crown  Point  Xos.  4,  5,  and  6, 
in  Sec.  5,  T.  10  X.,  R.  8  W.  [See  Mon.  XIII,  U.  S.  G.  S., 
page  376;  Report  State  Mining  Bureau  of  Cal.,  XIII,  page 
603.]  In  former  years  rich  surface  pockets  were  worked  to 
advantage;  they  were  situated  adjacent  to  a  serpentine  belt, 
ha\-ing  general  strike  X.  48°  W.  [See  map  of  Maj-acmas  Dis- 
trict, and  Fig.  37.]  Two  tunnels  (A  and  B),  respectiveh-  325 
and  200  feet  long,  and  a  shaft  (C)  50  feet  deep  with  a  drift  40 
feet  long  in  the  bottom,  represent  the  later  development  work, 
which  has,  however,  as  ^-et  not  disclosed  any  valuable  ore 
bodies.  This  work  has  been  done  in  a  very  unsystematic 
manner  and  proves  little  or  nothing  as  to  the  future  of  the 
property.  The  company  started  in  the  fall  of  1902  some  sj^s- 
tematic  prospecting  work. 

Culver-Baer  Mine. — Mayacmas  District.  This  is  in  Sees.  24, 
23,  and  14,  T.  II  X..  R.  9  \V..  along  the  headwaters  of  the 
north  fork  of  Little  Sulphur  Creek  (Devil's  Den  Canon). 
It  includes  the  Fairfax,  Sunny  Side,  Republic,  Bush,  Colfax, 
and  Culver-Baer  Xo.  i  and  Xo.  2  claims,  representing  the 
former  Oakland  and  Geyser  group;  and  the  L'nion,  Hard- 
scrabble,  Ridge,  Black  Bear,  and  West  End  claims,  representing 


< 


p:  1 

1 

5 

? 

u^ 

^ 

'^ 

^y<p.    ^ 

\^. 

\, 

104 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


the  Black  Bear  and  Kentuck  group.  Owner,  the  Culver- 
Baer  Mining  Company;  president,  A.  V.  McNabb,  vSanta  Rosa, 
Sonoma  Count^^;  general  manager,  G.  B.  Baer.  Cloverdale, 
Sonoma  County;  superintendent,  F.  Baumeister,  The  Geysers, 
Sonoma  County. 

This  property  covers  the  old  mines  of  the  Oakland  and 
Black  Bear  group.  This  mine  was  a  producer  from  1875  to 
1879,  producing  about  6900  flasks,  but  was  then  shut  down, 


' Sa  ^icLsto  ^le. 


Fig,  38.    Section  Culver-Baer  Mine. 

work  being  resumed  only  in  1901.  [See  Mon.  XIII,  U.  S.  G.  S., 
page  376;  Report  State  Mining  Bureau  of  Cal.,  XII,  page  371; 
XIII,  page  602.]  The  ledge  is  indicated  by  a  persistent  and 
very  strong  cropping  of  ledge  matter,  with  a  general  east  and 
west  course,  on  the  north  bank  of  the  canon,  about  150  feet 
wide,  dipping  north  into  the  mountain,  winding  a  little  but 
following  rather  closely  a  line  parallel  to  the  creek.  [See 
Fig.  38.]  These  croppings  consist  mostly  of  silicified  foot- wall 
sandstone,  changed  into  a  blocky  material  with  a  great  num- 
ber of  quartz  seams;  sometimes   serpentine    (hanging   wall), 


SONOMA    COUNTY.  105 

also  traversed  bj^  quartz  seams,  occurs.  This  ledge  material  is 
rather  hard  and  compact.  The  ore  is  not  making  on  the  faces, 
but  mosth^  inside  the  rock;  often  while  not  appearing  on  the 
surface,  the  pieces  of  rock  prove  rich  in  cinnabar  when  broken 
up.  Very  little  sulphide  of  iron  accompanies  the  cinnabar. 
Especialh-  in  the  old  Geyser  claim,  about  opposite  the  new 
furnace  site,  the  cinnabar  occurs  in  its  rarer  form  of  crystalliza- 
tion in  acicular  (needle-shaped)  prisms.  Higher  up  the  canon, 
in  the  old  Lost  Ledge  ground,  the  cinnabar  occurs  in  the 
ordinary  tabular  crystal  form. 

The  old  underground  works  in  the  Old  Oakland  and  Geyser 
group  are  caved  in,  and  a  crosscut  tunnel  driven  by  the  pres- 
ent company  is  also  inaccessible.  This  tunnel,  890  feet  long, 
is  on  the  level  of  the  new  furnace,  reaching  the  ledge  at  a 
depth  of  375  feet  below  the  old  croppings,  where  it  found  ore. 
The  old  works  on  the  Lost  Ledge  ground  (upper  part  of  the 
property)  reached  the  same  depth  in  the  ore  body. 

The  sandstone  foot  wall  along  the  ledge  is  greatlj'  eroded, 
forming  the  creek.  On  the  hanging  wall  is  a  narrow  belt  of 
serpentine  overlaid  by  a  wide  belt  of  sandstone.  This  belt  of 
serpentine  seems  to  persistently  accompany  the  outcrop.  The 
amount  of  ore  in  sight  in  the  croppings,  that  can  be  quarried,  is 
so  large  that  the  company  is  erecting  a  20-ton  Fitzgerald  incline 
furnace,  without  undertaking  for  the  present  anj-  further 
underground  development  work. 

The  western  part  of  the  property,  the  Black  Bear  group, 
covering  the  Old  Kentuck  ground,  has  been  leased  to  W.  T. 
Brush  and  others,  of  Cloverdale,  Sonoma  County. 

The  croppings  so  prominent  in  the  eastern  part  follow  Devil's 
Den  Caflon  into  the  Clyde  mine,  then  turn  a  little  northward 
and  re-enter  the  Black  Bear  group.  In  its  western  part  they 
are  abruptly  cut  off  by  a  body  of  serpentine,  having  a  nearly 
east  and  west  course.  The  present  lessees  are  cleaning  out 
some  of  the  old  works. 

Double  Star  Mine, — Mayacmas  District.  In  Sees.  2,  3,  10,  and 
1 1,  T.  10  N.,  R.  8  W.  The  property  is  on  the  old  road  from 
Middletown  to  Pine  Flat,  at  the  headwaters  of  Little  Sulphur 
Creek,  and  consists  of  the  Double  Star  Nos.  i,  2,  and  3,  Her- 
cules, and  Giant.  Owners,  Wm.  Peters,  of  Healdsburg, 
Sonoma  County,  and  others.     A  vertical   shaft  was  sunlc   on 


106  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

croppings  identical  with  those  on  Pine  Mountain,  the  Wall 
Street,  etc.;  it  has  been  abandoned  and  a  crosscut  tunnel  run 
1 70  feet  below  its  collar,  in  the  serpentine,  which  at  400  feet 
from  its  entrance  cut  the  fissure  on  which  the  shaft  was  sunk. 
Short  drifts  were  run  both  ways  on  the  fissure,  showing  the 
same  material  as  on  the  surface,  but  no  cinnabar  ore.  At  650 
feet  the  tunnel  reached  sandstone,  mixed  with  "alta";  drifts 
were  run  both  waj-s  on  the  supposed  contact,  without  dis- 
closing any  ore.  The  breast  of  the  tunnel  at  670  feet  is  in 
mixed  sandstone,  gouge,  and  decomposed  serpentine.  It  is,  in 
fact,  doubtful  if  the  real  sandstone  has  as  yet  been  reached. 

Eureka  Mine. — Mayacmas  District,  In  Sec.  32,  T.  11  N., 
R.  8  W.,  on  the  divide  between  Big  Sulphur  and  Little  Sulphur 
creeks,  to  the  northwest  of  the  Socrates  mine.  Includes  the 
Eureka  No.  i  and  No.  2  (Old  Flagstaff),  Mate,  and  Captain 
claims,  and  Eureka  millsites;  and  the  Electric,  Creekside, 
Trout,  and  King  Arthur  claims  in  Big  Sulphur  Creek,  in  Sec. 
29,  T.  II  N.,  R.  8  W.  Owner,  Eureka  Quicksilver  Mining 
Company;  C.  R.  Cormack,  secretary.  No.  215  Sansome  street, 
San  Francisco.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  375.]  A 
belt  of  serpentine  passes  through  the  southern  part  of  the 
Eureka  claims  near  the  ridge  of  the  hill,  with  a  general  strike 
about  northwest,  and  a  southwesterly  dip.  [See  Fig.  39.]  This 
serpentine  forms  the  hanging  wall  of  a  contact,  the  foot  wall 
being  sandstone.  In  the  main  tunnel,  this  arkose  sandstone  is 
very  much  decomposed,  the  silicates  having  been  largely 
altered  to  clay  by  weathering.  On  the  foot  wall  lies  a  heavy 
gouge,  and  the  ledge  matter,  which  is  cut  at  a  depth  of  170 
feet,  is  very  hard.  In  a  higher  tunnel  verj^  fair  ore  was  found, 
the  material  being  much  softer.  Two  drifts  have  been  run 
from  the  main  tunnel  along  the  ledge,  but  have  not  as  yet  reached 
any  pay  shoot.  The  hillside  is  very  steep,  and  heavy  slides 
have  occurred.  The  two  bodies  of  thinly-bedded  material 
(probably  chert) — one  in  the  Captain,  with  a  strike  of  N.  77°  E., 
the  other  higher  up  the  hillside  on  the  Eureka  No.  i,  strike 
N.  23°  W. — belonged  probably  to  the  ore  body. 

Lower  down  in  the  Mate  is  a  body  of  very  light- colored, 
loose-grained  sandstone,  carrying  quicksilver  in  the  form  of 
cinnabar  and  of  incrustations  of  black  sulphide  of  mercury. 
Sufficient  work  has  not  yet  been  done  on  this  material  to  decide 


SONOMA    COUNTY. 


107 


^ — 

"%] 

/ 

_^-— — T^r-^     '' 

1 

/ 

^^--^-^ — ^^    /    V"= '' 

/          "5 

^  / 

r"            /   ^  V  \ 

^ 

«/ 

/                          /         ''■s  — ' 

/           "Q 

1 

/        ■     /•     ^'^"^'^ 

/          '^ 

/ 

/               /l     ^'4 

/ 

/ 

/                                                /  ^                  cs'^  ^ 

/       ^J^^^ 

- —                                 '■■S 

L     Itt 

\^ 

tJ 

/                           ^                         />r>                                5  -  ' 

1 

s 

1               '"^ 

'"  1 

•> 

^    00    ' 
ct 

H 

« 

^< 

5  °° 

0  ^ 

-^ 

/                       'Ti^\J^^^'-^^^     \ 

o 

'J 

'  o 

/ 

H 

-J 
< 
o 
w 

rt 

\        \  "K-k  )  '^      \ 

\          <0       ol 

't 

1  ..ir''''^"''  '^'^•'/n/'nA  1      <M 

\.,, 

§ 

5: 

\        ''          "   ~  A'         ^ 

\        \ 

5 

\  y     v-kix    ^ 

\ 

« 

i2 

\     -^                                                c    ^      ft    \ 

\ 

.  t 

Q 

A                      ?r'.l°\1           a?^ 

\ 

1 

°    .5; 

\ 

1 

\                                      \v,             3 

\ 

<J 

\       -        r     ^ 

\ 

J.  "^ 

\                     Q                      V'^ 

\ 

« 

\          ^            V 

\ 

V    . 

OCj^___^ 

1, 

\                    o£i— ^''' — 

108 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


about  the  extent  and  importance  of  this  deposit  of  quicksilver 
ore.  A  thin  seam  of  cinnabar  ore,  three  inches  wide  at  the 
surface,  has  been  cut  by  a  tunnel  at  a  depth  of  about  30  feet, 
showing  a  width  of  one  foot.  The  mine  is  equipped  with  a 
20-ton  Fitzgerald  furnace,  built  in  the  latter  part  of  1902. 

Great  Eastern  and  Mount  Jackson  Mines.— Near  Guerneville. 
The  Great  Eastern  Quicksilver  Mining  Company,  owner; 
A.  Abbey,  superintendent,  Mercury,  Sonoma  County :  or  No.  44 
Nevada  Block,  San  Francisco.     In  Sees.  16  and   17,  T.  8  N., 


Fig.  41.     Section  over  the  Great  Eastern  Mine. 

R.  10  W.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  362;  Report 
State  Mining  Bureau  of  Cal.,  VIII,  page  633;  XI,  page  460; 
XIII,  page  602.]  These  mines  are  peculiar  in  so  far  that  they 
are  at  a  considerable  aistance  from  all  other  workable  deposits 
and  also  from  any  known  eruptives.  The  outcrop  is  prominent, 
but  only  for  a  relative h'  short  distance  (about  1900  feet),  and 
follows  prett}'  closely  a  belt  of  serpentine  [see  Fig.  40],  cutting 
through  the  irregularly  metamorphosed  rocks  of  the  Coast 
Range,  probably  of  Neocomian  age.  The  strike  is  very  nearh' 
east  and  west — in  the  Great  Eastern,  N.  75°  \V.;  in  the  Mount 
Jackson,  N.  63°  W.  The  croppings  stand  almost  vertical  near 
the  surface,  but  in  depth  dip  northeasterly.     The  sandstone 


General   Plan    of 
GREAT  EASTERN  MINE. 


c/ierf^    beets 


coar.je 

■s.s. 


0  <  ^'', 


:c^,^v.'„„„„.v^^^"^,;^';-/^,.< 


-;"'_  '<-  '-''        \}''^^Or,-J''-'~~    -  '''/  coarse  ^    c:.  ^ 


s 


^  40O' 


Soo 


FEEr 


I  I  Serpentine 

1  I  Cropjo/rjgs 


110  QUICKSILVER   RESOURCES   OF    CALIFORNIA. 

foot  wall  has  been  considerably  eroded,  leaving  the  croppings 
of  the  ledge  in  bold  relief.     [See  Fig.  41.] 

The  main  shaft  is  sunk  vertically  in  the  sandstone  foot  wall 
to  a  depth  of  500  feet,  and  the  cross  drifts  from  the  shaft  to  the 
vein  on  the  various  levels  show  that  no  serpentine  occurs  in 
the  foot  wall.  The  hanging  wall  is  serpentine.  The  croppings 
[see  Fig.  41]  are  about  200  feet  above  the  level  of  the  shaft, 
and  were  worked  through  several  drifts  and  cuts.  At  present 
all  the  ore  comes  from  the  lower  levels. 

On  the  500-foot  level,  a  detached  ore  body  has  been  found, 
120  feet  southwest  of  the  main  ore  vein,  in  the  foot-wall  sand- 
stone, and  has  been  opened  up  for  about  60  feet,  showing 
good  ore.  A  raise  20  feet  high  shows  that  the  top  of  this  ore 
body  pitches  southeasterly  on  a  strike  nearly  parallel  to  that 
of  the  main  vein.  The  vein  filling  is  ven,"  similar  to  that  of 
the  main  vein.  The  country  adjacent  to  the  deposit  carries 
a  considerable  amount  of  iron  pyrites;  strong  emanations  of 
fire  gas  render  work  in  this  vein  ver}-  diflScult,  as  this  gas 
attacks  the  eyes  of  the  miners.  Efforts  have  been  made  to 
collect  this  gas  for  analysis,  but  as  yet  have  not  succeeded. 
On  the  same  level,  inten-ening  between  the  main  ledge  and 
the  serpentine  hanging  wall,  is  a  ver>'  hard  crystalline  rock  of 
a  graj'ish  color,  showing  some  slight  signs  of  serpentinization, 
but  having  no  resemblance  to  the  chalcedonite  found  in  other 
quicksilver  deposits.  This  hard  rock  has  the  advantage  of 
allowing  the  large  stopes  to  be  left  without  timbering  or  fill- 
ing, notwithstanding  the  mine  makes  considerable  water.  On 
one  ore  body  the  stope,  from  10  to  35  feet  wide,  is  carried  to 
the  surface,  being  sustained  by  rock  pillars  left  in  the  poorer 
parts  of  the  ledge,  Avithout  any  stulling  or  filling.  The  same 
stope  is  continued  downward  about  90  feet  below  the  500 -foot 
level. 

A  vertical  shaft  is  sunk,  starting  from  the  500-foot  level,  on 
the  ledge,  about  100  feet  deep.  At  the  bottom  of  the  shaft  in 
the  5So-foot  level  the  foot  wall  shows  very  plainly;  the  ore 
makes  in  places  clear  to  that  wall  with  very  little  or  no 
gangue.  Between  the  ore-carrying  zone  and  the  serpentine 
hanging  wall  comes  first  the  hard  siliceous  rock  casing  above 
described,  then  a  much  softer  zone  of  somewhat  decomposed 
serpentine,  and  then  the  hanging- wall  serpentine.    [See  Fig.  41 .] 


SONOMA    COUNTY. 


Ill 


The  ore  forms  in  irregular  lenticular  bodies,  more  persistent 
vertically  than  horizontall3\     [See  Fig.  42.] 

The  ledge  filling  is  generally  a  very  hard  crystalline  rock, 
fissured  and  cross-fissured  in  all  directions,  and  recemented  by 
subsequent  depositions.  The  ore  forms  principallj'  in  relativelj^ 
softer  zones  in  this  material.  It  carries  less  iron  pj-rites  in  the 
lower  levels  than  at  the  surface,  and  the  exudations  of  sulpho- 
salts  are  also  much  less  in  the  lower  levels,  rendering  the 
ventilation  of  the  mine  a  relatively  easy  matter.  In  the  ledge 
filling  are  found  bunches  of  soft,  whitish,  somewhat  unctuous 
material — a  decomposition  product.  It  is  impossible,  due  to 
the  complete  decomposition,  to  determine  the  character  of  the 
original  material.  The  material,  locally  called  "caliche,"  is 
sometimes  barren,  and  sometimes  carries  sensible  amounts  of 


Fig.  42.     Great  Eastern  Mine— Plau  showing  the  form  of  the  ore  bodies. 

cinnabar,  but  its  presence  generally  indicates  the  proximity  of 
cinnabar  deposits.  On  the  580-foot  level  an  exposure  of  the 
crj'stalline  fissured  rock  carrying  cinnabar  shows  that  some  of 
these  fissures  are  rather  wide,  over  an  eighth  of  an  inch,  and 
that  the  rock  is  recemented  by  quartz  containing  no  signs  of 
cinnabar.  Clearly,  then,  this  recementation  took  place  subse- 
quent to  the  cinnabar  deposition. 

The  absence  of  gangue,  the  hard  siliceous  material  on  the 
hanging  wall,  and  the  character  of  the  vein  filling,  all  indicate 
a  very  strong  silicification  (cementation)  process,  but  of  an 
entirely  different  nature  from  that  forming  the  chalcedonite 
"  quicksilver  rock "  so  often  associated  with  cinnabar  deposits. 
In  the  levels  above  the  collar  of  the  shaft  in  the  surface  crop- 
pings  some  opaline  rock  is  found,  and  the  silicification  (cemen- 


112  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

tationj  of  the  ledge  matter  is  less  distinct  than  in  the  lower 
levels. 

The  mine  is  equipped  with  one  12-ton  coarse-ore  Maxwell 
furnace,  and  one  16-ton  fine-ore  Hiittner  &  Scott  furnace,  using 
brick  and  wooden  condensers. 

Great  Northern  Company ♦ — Mayacmas  District.  W.  H.  Jordan, 
president,  Xo.  131 1  Claus  Spreckels  Building,  San  Francisco. 
Owns  nine  claims — Alta,  Leota,  r^Iinaoka,  Little  Giant,  Colum- 
bia, Bluejay,  Happ}'  Hooligan,  Wizard,  and ,  in  Sec.  2, 

T.  10  N.,  R.  8  W.,  and  Sec.  33.  T.  11  X.,  R.  8  \V.,  situated  north- 
east and  parallel  to  the  Old  Denver.  Xo  important  develop- 
ment work  has  as  j-et  been  done  on  this  property. 

Hope  Mine. — Mayacmas  District.  Crown  Point  Quicksilver 
Mining  Company,  owner;  S.  S.  Bogle,  secretary-,  Santa  Rosa, 
Sonoma  County.  Includes  the  Hope  Xos.  i,  2,  and  3  mines,  in 
Sec.  4,  T.,io  X.,  R.  8  \V.  This  group  is  on  the  southeastern 
extension  of  the  Eureka  and  Socrates  belt  of  croppings.  The 
Hope  shaft,  very  near  the  northwestern  end  line,  is  80  feet 
deep,  sunk  on  these  croppings,  but  at  present  is  inaccessible. 
A  tunnel  has  been  run  partly  on  the  contact  and  partly  in  the 
serpentine  hanging  wall.  The  ledge  filling  is  a  siliceous 
material,  with  a  main  Assuring  parallel  to  the  strike.  At  the 
breast  a  crosscut  shows  that  this  fissure  filling  is  30  feet  wide. 
At  the  southeast  end  of  this  crosscut  a  winze  15  feet  deep  has 
been  sunk,  but  is  at  present  caved  in.  There  are  ver>'  few 
signs  of  cinnabar  in  the  tunnel  or  in  the  material  on  the  dump. 

Hurley  Property. — Mayacmas  District.  Mrs.  M.  Hurley,  1820 
Pacific  avenue,  San  Francisco,  owner.  The  property  consists 
of  160  acres  in  Sees.  4  and  5.  T.  10  X.,  R.  8  W.,  to  the 
southeast  of  the  old  Sonoma  mine.  In  this  property  is  found 
the  continuation  of  the  serpentine  belt  running  through 
the  Sonoma,  associated  on  both  sides  wnth  sandstones.  A 
short  surface  tunnel  near  the  falls  of  the  creek,  close  to  the 
west  line  of  the  property,  shows  a  ledge  having  a  course  nearly 
X.  45°  W.,  about  30  feet  wide,  dipping  westward.  The  serpen- 
tine belt  on  the  property  is  generally  prett}'  narrow.  Xear  the 
house  in  the  east  and  west  center  of  the  property  some  crop- 
pings show  on  the  surface;  on  these  are  a  shaft  50  feet  deep 
and  a  caved-in  tunnel  150  feet  long.  It  is  claimed  that  some 
cinnabar  ore  w^as  found  in  the  bottom  of  the  shaft. 


SONOMA    COUNTY.  113 

Lookout  Group. — Mayacmas  District.  Judson  Brown,  Pine 
Flat,  Sonoma  Count}',  owner.  Includes  the  Lookout  and 
Diamond  claims,  in  Sec.  32,  T.  11  N.,  R.  8  W.;  parallel  and 
adjoining  the  Eureka  Nos.  i  and  2  to  the  south.  No  develop- 
ment of  any  importance. 

Lucky  Stone  Group. — Mayacmas  District.  C.  A.  Grimmer, 
Pine  Flat,  Sonoma  County,  owner.  Includes  the  Last  Chance, 
Pay  Reef,  and  Mother  Lode  claims,  in  Sec.  4,  T.  10  N.,  R.  8  W., 
lying  parallel  and  adjoining  the  Old  Denver  to  the  southwest. 
On  the  Last  Chance,  the  most  northwesterly  claim,  old  work- 
ings show  some  cinnabar  ore  on  the  contact  of  serpentine  and 
sandstone. 

Maricoma  Mine  (Santa  Rita). — E.  White  and  others,  of  Pine 
Flat,  Sonoma  County,  owners.  In  Sec.  36,  T.  10  N.,  R.  8  W. 
Three  tunnels  have  been  run  on  this  property;  the  upper  one 
is  160  feet  above  the  level  of  the  lower  tunnel.  In  the  lower 
tunnel  a  stope  has  been  raised  on  an  ore  body  about  6  feet 
wide,  having  a  serpentine  foot  wall  and  a  sandstone  hanging 
wall,  with  a  wide  gouge  on  the  foot  wall,  and  containing  some 
good  cinnabar  ore.  In  the  breast  of  the  tunnel  the  contact 
carries  no  cinnabar  ore. 

Mercury  Mining  Company. — Macaymas  District.  F.  A.  Hunt- 
ington, president.  No.  330  Montgomery  street,  San  Francisco. 
Owns  the  Boulevard,  Boulevard  Extension,  Elizabeth,  Espe- 
ranza,  and  two  other  claims  northeast  of  the  Socrates  mine, 
and  the  Prince  and  Princess  southwest  thereof.  In  Sees.  32 
and  33,  T.  11  N.,  R.  8  W.,  and  Sec.  2,  T.  10  N.,  R.  8  W.  No 
important  development  work  has  as  yet  been  done  on  this 
property. 

Missouri  Mine. — Mayacmas  District.  L.  W.  Pittman,  The 
Geysers,  Sonoma  County,  owner.  In  Sec.  25,  T.  1 1  N.,  R.  9  W. 
[See  Mon.  XIII,  U.  S.  G.  S.,  page  376;  Report  vState  Mining 
Bureau  of  Cal.,  XIII,  page  603.]  It  lies  to  the  northeast 
of  the  Culver- Baer  propert}'.  This  mine  has  been  idle  for 
years  and  all  workings  are  inaccessible.  The  Culver-Baer 
Company  is  cleaning  out  some  of  these  works  to  test  the  value 
of  the  property. 

Napa    Mine. — Mayacmas    District.     In    Sec.    11,  T.    10  N., 
R.   s  W.     Donzel  Stoney,  40    Montgomery  street,  San  Fran- 
cisco, owner.     Idle. 
8— QR 


114  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

Occidental  and  Healdsburg  Group. — Mayacmas  District.  In 
Sec.  lo,  T.  lo  N.,  R.  8  W.  J.  Stern,  No.  lo  Battery  street, 
San  Francisco,  owner.     Idle. 

Old  Chapman  Mine. — W.  A.  Coalson,  of  Alexander,  Sonoma 
County,  owner.  It  lies  in  Sees.  25  and  30,  T.  10  N.,  R.  8  W., 
at  the  mouth  of  Sausal  Creek  canon,  on  Deer  Creek.  On  the 
south  side  of  Deer  Creek  a  line  of  croppings,  course  about 
N.  15°  W.,  runs  down  the  slope  toward  the  creek,  but  the 
underground  works  have  not  disclosed  any  continuation  of 
ore  in  depth. 

Pacific  Mines  (Crystal  or  Red  Cloud). — Mayacmas  District.  In 
Sees.  5  and  6,  T.  10  N.,  R.  8  W.  This,  the  northwestern 
extension  of  the  Sonoma  mine,  comprises  the  Crystal,  Crystal 
No.  2,  Crystal  Extension  Nos.  i,  2,  3,  and  4.  Owner,  Pacific 
Mining  Company;  A.  Abbey,  611  Market  street,  Oakland; 
A.  Anderson,  superintendent,  Pine  Flat,  Sonoma  County.  [See 
Mon.  XIII,  U.  S.  G.  S.,  page  376;  Report  State  Mining  Bureau 
of  Cal.,  XIII,  page  603.]  The  country  rock  is  mostly  altered 
sandstone,  through  which  the  same  belt  of  serpentine  which  is 
found  in  the  northwestern  part  of  the  Sonoma  mine  runs  in 
about  the  same  strike,  N.  48°  W.  [See  Fig.  37.]  On  the  sur- 
face some  croppings  show  at  the  southwestern  contact  of  this 
serpentine  belt  with  the  sandstone.  A  crosscut  tunnel  (Pacific 
tunnel),  direction  nearly  north,  runs  265  feet  below  these  crop- 
pings. Starting  in  the  countr}'  rock  southwest  of  the  serpen- 
tine, it  cuts  through  another  belt  of  serpentine  40  feet  wide, 
150  feet  from  the  mouth,  to  the  north  of  which  is  60  feet  of 
broken  ledge  matter  (called  the  Little  Vein),  upon  which, 
however,  no  work  has  been  done.  At  525  feet  the  tunnel 
reaches  the  foot- wall  gouge,  then  goes  through  25  feet  of  very 
much  broken  ledge  matter,  and  at  550  feet  reaches  the  serpen- 
tine hanging  wall,  here  about  75  feet  wide.  Short  drifts  have 
been  run  both  ways  along  the  hanging  wall,  but  no  workable 
ore  bodies  have  as  3'et  been  found.  The  same  contact  has  been 
found  in  other  workings;  the  croppings  show  plainly  along  the 
crest  of  the  ridge.  A  tunnel  (A)  running  along  the  vein,  and 
starting  at  the  southeast  end  of  the  hill,  about  66  feet  above 
the  level  of  the  Pacific  tunnel,  has  disclosed  some  promising 
ore.  In  this  tunnel  a  shaft  40  feet  deep  has  been  sunk,  which 
shows  some  very  good  ore.     Another  tunnel  ( A^),  about  40  feet 


SONOMA    COUNTY.  115 

lower,  and  nearly  parallel  to  tunnel  A,  has  not  yet  connected 
with  this  shaft. 

Pontiac  Group. — Mayacmas  District.  H.  S.  Beach  and  E. 
Warner,  of  Pine  Flat,  Sonoma  County,  and  C.  Mobley,  of 
Healdsburg,  Sonoma  County,  owners.  Consisting  of  four 
claims:  Pontiac  Nos.  i,  2,  3,  and  4,  in  Sees.  33  and  34,  T.  11  N., 
R.  8  \V.  No  important  development  work  has  as  yet  been 
done  on  this  propert}'. 

Rattlesnake. — Mayacmas  District.  H.  C.  Lightner,  Parrott 
Estate,  San  Francisco,  and  others,  owners.  In  Sec.  31,  T.  11 
N.,  R.  8  W.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  376;  Report 
State  Mining  Bureau  of  Cal.,  XIII,  page  603.]  This  mine  was 
worked  in  1S74,  but  is  at  present  abandoned  and  the  workings 
are  inaccessible.  In  this  mine  the  mercury  was  nearly  exclu- 
sively found  in  the  native  state,  as  in  the  Socrates.  The  country 
rock,  judging  from  the  surface,  is  altered  sedimentaries,  with 
occasional  small  occurrences  of  serpentine. 

Socrates  Mine. — Mayacmas  District.  In  Sees.  32  and  33, 
T.  II  N.,  R.  8  W.,  and  Sees.  4  and  5,  T.  10  N.,  R.  8  W.  It  is 
on  the  divide  between  Big  Sulphur  and  Eittle  Sulphur  creeks, 
where  the  road  from  Calistoga  to  The  Geysers  crosses.  Owners, 
W.  H.  Jordan,  No.  131 1  Claus  Spreckels  Building,  San  Fran- 
cisco, F.  A.  Huntington,  and  T.  W.  Nowlin;  H.  Davey,  super- 
intendent, Guadalupe  mine,  Santa  Clara  County.  This  ledge 
is  on  the  same  contact  as  the  Eureka  mine;  the  croppings  show 
very  prominently  and  can  be  traced  for  a  considerable  distance 
between  the  sandstone  foot  wall  and  the  serpentine  hanging 
wall.  The  main  tunnel  [see  Fig.  43]  is  run  at  a  depth  of  about 
200  feet  below  the  top  of  the  ridge,  starting  in  the  foot  wall 
material,  which  is  decomposed  sandstone  mixed  with  shale  and 
clay.  The  average  strike  of  the  ledge  is  northwest,  but  the 
gouge  on  the  foot  wall,  which  in  the  Eureka  mine  is  very  wide, 
is  much  thinner;  the  ledge  matter  is  soft  opaline  rock,  very 
much  fractured  and  favorable  to  ore  deposition.  The  quick- 
.silver  occurs  mainly  as  native  mercury,  the  fractures  of  the 
opaline  rock  being  filled  with  native  mercury  and  some  cinna- 
bar, the  more  compact  portion  of  the  rock  containing  minute 
globules  of  native  mercury.  A  "horse"  of  serpentine  about 
2  feet  wide  runs  through  the  vein.  The  ore  on  the  foot-wall 
gouge  is  softer  and  generally  richer.     In  some  places  bunches 


116 


QUICKSILVER    RESOURCES    OF    CALIFORXIA. 


of  native  mercurj-  are  found  in  the  sandstone,  especially  in  the 
southeast  drift.  The  foot-wall  black  gouge  carries  oxides  of 
iron,  calcium  and  magnesium,  silica,  silicate  of  magnesium, 
and  some  free  gases  (probably  free  sulphide  of  h5'drogen  and 
carbon  monoxide),  which  are  ver}-  noxious  to  the  miners.  The 
occurrence  of  the  quicksilver  almost  exclusively  in  the  native 
state  causes  unhealthy  conditions  underground  and  great  loss  of 
mercury  in  blasting  and  handling  the  rock;  the  recovery  of  the 
mercur}'  from  the  ore  is  also  a  problem,  which  has  as  yet  been 
only  partially  solved. 

At  present  the  compau}-  is  passing  the  ore  through  a  rotarj" 
roaster,  27  feet  long,  5  feet  8  inches  in  diameter,  lined  with 
lo-inch  firebrick,  having  a  pitch  of  6  inches,  using  wood  as  a 


Fig    ^3.     Socrates  Mine. 

fuel.  The  rotation  is  very  slow,  and  the  draft  is  so  regulated 
as  to  control  the  amount  of  oxygen  permitted  to  enter  the  fur- 
nace. From  this  roaster  the  vapors  pass  through  a  series  of 
condensers  to  the  stack,  where  it  is  claimed  that  the  products 
of  combustion  exhaust  at  100°  F.  The  results  appear  to  be 
very  satisfactory  to  the  owners. 

Walker  Mine. — Near  Guerneville,  in  Sec.  7,  T.  S  N.,  R.  10  W. 
L.  F.  Walker,  of  Guerneville,  Sonoma  County,  and  M.  C. 
Meeker,  of  Camp  Meeker,  Sonoma  County,  owners.  Some 
surface  deposits  caused  a  tunnel  560  feet  to  be  driven  into  the 
mountain,  which  at  415  feet  from  its  mouth  crosscuts  for  60 
feet  a  material  showing  signs  of  strong  silicifacation,  and  then 
runs  along  the  supposed  center  of  this  material  for  about  90 
feet. 


YOLO    COUNTY.  117 

Wall  Springs  Mine.  -  Near  Guerneville,  in  Sec.  30,  T.  S  N., 
R.  9  W.  H.  C.  Wall,  Hilton,  Sonoma  County,  owner;  Healds- 
burg  Quicksilver  Mining  Company,  J.  C.  Hobson,  of  Hilton, 
Sonoma  County,  lessee.  A  shaft,  70  feet  deep,  is  in  process 
of  sinking.  It  is  claimed  that  the  surface  material  (serpen- 
tine) carries  cinnabar,  but  in  the  material  excavated  from  the 
shaft  no  signs  of  cinnabar  could  be  detected. 

YOLO  COUNTY. 

New  England  and  Harrison  Mines.— Knoxville  District.  The 
New  England  is  in  Sec.  26,  T.  12  N.,  R.  5  W.,  and  the  Har- 
rison is  in  Sec.  35,  T.  12  N.,  R.  5  W.;  the  latter  most 
probably  covering  the  ground  of  the  Grizzly,  mentioned  by 
Becker.  M.  W.  Harrison,  Knoxville,  Napa  County,  owner. 
[See  Report  State  Mining  Bureau  of  Cal.,  XII,  page  363; 
XIII,  page  598.]  Both  mines  lie  in  serpentine.  The  minerali- 
zation is  accompanied  with  silicification,  forming  a  verj'  hard 
opaline  material. 

In  the  New  England  are  abundant  signs  of  decomposition 
by  sulphuric  waters.  Small  blisters  with  an  eggshell  envelope, 
containing  oil  and  sulphur,  are  found  in  the  rock.  Up  to  the 
present  time,  nothing  of  value  has  been  exposed  in  this  mine. 

The  Harrison  tunnel  was  inaccessible.  The  dump  shows 
the  ledge  matter  to  be  a  very  hard  opaline,  carrying  some  cr\^s- 
tals  of  cinnabar  in  the  seams. 

In  the  wide  serpentine  belt  to  the  southwest  of  the  Manhat- 
tan-Boston line  occur  croppings  of  opaline  rock  which  have 
been  prospected  for  years  without  any  result. 

Reed  Mine. — Knoxville  District.  Including  the  Royal  or 
Soda  Springs  mine.  Merchants  Exchange  Bank,  San  Fran- 
cisco, owner.  In  Sees.  23,  25,  26,  and  36,  T  12  N.,  R.  5  W, 
[See  Mon.  XIII,  U.  S.  G.  S.,  page  283;  Report  State  Mining 
Bureau  of  Cal,  XI,  page  68.]  This  property  was  extensively 
worked,  producing  5650  flasks  between  1875  and  1879,  but  has 
been  idle  for  a  number  of  years.  The  works  are  caved  in  and 
inaccessible.  The  surface  geology  shows  that  the  deposits  in 
the  Reed  mine  are  located  close  to  the  line  of  contact  of  an 
area  of  serpentine  with  unaltered  fossiliferous  rocks,  the  ore 
bodies  being  contained  in  an  opaline  rock  formation.  The  old 
works  of  the  Royal  mine  are  located  on  a  dike  of  the  same 
material,  20  feet  wide,  cutting  through  the  serpentine. 


Cropptngs 


MAP  OF  THE  LITTLE  PANOCHE  MINING  DISTRICT. 


DISTRICTS   SOUTH   OF    SAN    FRANQSCO. 


FRESNO  COUNTY. 

Arambide  and  Aurecoechea  Claims.— These  are  in  Sec.  32, 
T.  13  S.,  R.  10  E.,  and  Sec.  5,  T.  14  S.,  R.  10  E.  Owner,  George 
Alferitz,  care  of  Dellepiane  &  Co.,  425  Battery  street,  San 
Francisco.  These  claims  are  situated  near  the  Providential 
group  of  mines  [see  map  of  Little  Panoche  Mining  District] , 
in  the  same  formation  of  metamorphic  sandstone,  mixed  with 
some  shale.  In  former  3'ears  considerable  mercury  was  taken 
out  of  this  property,  but  the  works  are  now  caved  in  and  inac- 
cessible, and  the  furnace  is  entirely  obliterated. 

Mexican  Mine. — This  comprises  three  claims  (Mexican  Mine 
Xos.  I,  2,  and  3),  in  N.E.  %  of  Sec.  22,  T.  18  S.,  R.  13  E. 
Owner,  Manuel  Santos,  New  Idria,  San  Benito  County.  The 
developed  part  of  the  property  lies  in  the  northwest  branch  of 
Cantua  Creek,  very  close  to  the  contact  of  the  metamorphic 
series  and  the  Chico  sandstones  to  the  northeast  thereof. 
While  the  surface  shows  almost  exclusively  serpentine,  the 
underground  workings  have  proven  that  this  rock  is  in  places 
only  a  surface  covering,  the  tunnels  all  passing  the  serpentine 
in  from  10  to  15  feet  and  entering  into  sandstone. 

Tunnel  No.  i  [see  Fig.  44]  is  a  short  tunnel  in  sandstone, 
heavily  bedded,  with  a  strike  N.  13°  W.,  dip  S.W.  80°,  through 
which  a  seam  6  inches  wide  cuts  on  a  strike  N.  25°  W.,  dip 
N.E.  40°,  carrying  cinnabar  associated  with  silica  and  oxides 
of  iron,  oxidation  product  of  iron  sulphides. 

Tunnel  No.  2,  on  opposite  side  of  the  gulch,  after  passing 
through  10  feet  of  surface  serpentine  enters  into  sandstone. 
This  tunnel  has  a  course  south,  60  feet  long;  20  feet  in  a  side 
drift  runs  S.  45°  E.  about  30  feet,  which  cuts  a  narrow  seam 
of  ledge  matter,  course  S.  20°  W.  The  breast  of  the  tunnel 
follows  for  some  feet  a  fissure  from  18  to  24  inches  wide,  carry- 
ing cinnabar,  the  gangue  being  a  dark  yellov,'  ochery  material, 
indicating  that  the  unaltered  ore  will  be  found  to  carry  a  great 

(119) 


120 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


amount  of  iron  sulphide.     About  2   feet  from  the  breast  is  a 
shaft  30  feet  deep  on  a  narrow  seam  of  ore. 

A  little  above  a  line  from  Xo.  i  to  Xo.  2  in  the  gulch  is  an 
open  cut  8  feet  deep,  showing  fissures  in  the  sandstone,  dip- 
ping northeast,  filled  with  silica  and  seams  of  cinnabar  asso- 
ciated with  iron  sulphide. 


FIG  44. 
FLAN    or 

n£X/CAN  M/NE 

F/?fSNO    CO  UN  TV 


Below  and  to  the  northeast  of  these  works  in  the  gulch  are 
two  tunnels:  Xo.  4,  running  N.  10°  W.,  75  feet;  then  S.  So*^  \\'., 
50  feet;  projected  to  reach  under  Xo.  i.  This  tunnel  is  entirely 
in  slate,  but  at  the  breast  sandstone  is  coming  in  the  roof.  The 
lower  tunnel,  Xo.  5,  300  feet  long,  course  nearly  east  and 
west,  is  entirely  in  slate.  Xeither  of  these  tunnels  has  reached 
the  ore  deposits  as  yet. 


FRESNO    COUNTY.  121 

Providential  Group* — Owners,  Thomas  Flint,  J.  J.  Croxon, 
B.  P.  Stephenson,  N.  C.  Briggs,  A.  Johnson,  B.  Vargas,  of  Hol- 
lister,  San  Benito  County.  This  group  consists  of  seven  claims. 
[See  map  of  Little  Panoche  Mining  District.]  The  country  rock 
is  metamorphic  sandstone  intermixed  with  some  shale.  The 
strike  of  the  sandstone  is  prominently  north  and  south;  that 
of  the  shales  east  and  west.  The  sandstones  and  shales  have 
a  bluish-gray  color.  In  the  sandstone  occur  narrow,  irregular 
seams  of  white  quartz.  A  more  or  less  intricate  system  of 
leached  zones  runs  through  the  sandstone,  which  is  apparently 
leached  to  a  dull  white  color  by  the  action  of  some  percolating 
solution.  The  cinnabar  is  found  in  these  zones,  which  is 
accompanied  by  nearly  continuous  seams,  from  i  to  2  feet 
wide,  of  quartz  colored  brown  b}-  iron  and  in  places  forming  very 
large,  perfect  quartz  crystals,  indicating  a  deposition  in  open 
places.  The  zones  contain  a  great  amount  of  oxide  of  iron, 
forming  yellow  ocher  and  principall}'  red  oxide.  The  cinnabar 
is  found  intimately  associated  with  the  red  oxide.  The  crop- 
pings  are  prominently  indicated  by  the  quartz  seams.  The 
country  rock  is  soft  and  has  been  very  deeply  eroded  into  ver}' 
steep  and  deep  gulches,  and  the  course  of  the  ledges  is  in  places 
obscured  by  probable  slides.  Their  course  is  indicated  on  the 
accompanying  map.  The  material  is  ver}-  deceptive.  Rela- 
tively very  little  cinnabar  can  be  seen  in  the  ledge  filling,  even 
with  a  glass;  but  on  washing  the  material,  rich  in  disinte- 
grated iron  oxide,  proves  it  to  contain  considerable  amounts  of 
cinnabar. 

The  principal  work  has  been  done  on  the  Providential  and 
Gabilan  claims.  In  the  former  an  incline  shaft  has  been  sunk 
near  the  bottom  of  the  gulch  at  a  place  where  the  ledge  splits 
in  two.  This  shaft,  course  N.  74°  E.,  on  an  incline  of  about 
50°,  is  run  along  a  slip,  which  stands  nearly  vertical  and  shows 
considerable  cinnabar.  The  bottom  of  the  shaft  is  almost 
entirely  in  a  black  gouge.  A  drift  has  been  started  S.  74°  W'., 
to  undercut  the  ground  vertically  under  the  collar  of  the  shaft. 
The  sandstone  is  an  arkose,  nearly  unaltered  sandstone.  The 
work  on  the  Gabilan,  880  feet  higher,  is  on  the  top  of  the  main 
ridge;  there  is  a  shaft  about  25  feet  deep  and  some  shallow 
cuts,  showing  the  same  leached  sandstone,  wnth  the  quartz 
seam  running  through  the  center  of  the  mineralized  zone;  the 


122  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

course  of  the  ledge  is  here  X.  54^  E.,  the  dip  60^  southeasterly. 
Some  work  has  been  done  on  the  Buena  Vista,  southwest  of  the 
Providential,  showing  the  ledge  to  run  north,  dipping  east  60°, 
about  3  feet  wide.  The  connection  of  this  ledge  with  that  of 
the  Providential  can  not,  however,  be  traced  on  the  surface. 

KINGS  COUNTY. 

The  mine  (no  name)  in  the  X.W.  ^  of  the  S.W.  ^(  of 
Sec.  22,  T.  22  S.,  R.  16  E.,  belonging  to  F.  W.  Hunter,  C.  F. 
Francis,  and  G.  H.  French,  of  Parkfield,  Monterey  County,  is 
situated  on  Avenal  Creek,  east  of  Table  Mountain,  14  miles  from 
Parkfield.  The  mine  is  at  the  contact  of  the  serpentine  and 
the  Chico  sandstone.  This  contact  forms  a  mass  of  rubble, 
gravel,  and  partly  cemented  material,  intermixed  with  bowl- 
ders of  sandstone  and  serpentine,  and  claj-,  which  it  is  claimed 
on  washing  proves  to  contain  cinnabar.  There  is  a  gray 
sandstone  resembling  the  sandstone  carrj-ing  cinnabar  in  the 
Oceanic  mine,  which  also  here  shows  cinnabar.  This  material 
is  found  underlaid  by  cemented  gravel  pebbles. 

The  serpentine  on  the  south  bank  of  the  creek  has  all  the 
appearances  of  being  a  slide  from  the  side  of  Table  Mountain, 
and  has  apparently  pushed  up  the  adjoining  sandstone  beds 
and  been  partly  projected  within  those  beds.  The  countrj'^ 
has  no  mining  timber,  but  a  fair  supplj'  of  fuel  timber. 

The  mine  (no  name)  in  the  S.E.  J4  of  the  X.W.  }.{  of  Sec. 
28,  T.  22  S.,  R.  16  E.,  belonging  to  H.  Dawson,  of  Lemoore, 
Kings  County,  is  on  Table  Mountain,  13  miles  from  Parkfield, 
Monterey  County.  There  is  a  shaft  about  10  feet  deep  on 
some  fair  croppings,  but  showing  as  yet  no  permanent  forma- 
tion. 

The  mine  (no  name)  in  the  X.W.  ^4  and  X.  }4  of  the  S.W 
^  of  Sec.  28,  T.  22  S.,  R.  16  E.,  belonging  to  F.  \V.  Hunter, 
C.  F.  Francis,  and  G.  H.  French,  of  Parkfield,  Monterey  County, 
and  Mrs.  A.  Smith,  of  Lemoore,  Kings  County,  is  on  Table 
Mountain,  13  miles  from  Parkfield,  Monterey  County.  There 
are  a  number  of  shallow  surface  openings  on  croppings  which 
show  some  cinnabar,  but  in  no  place  has  any  permanent  forma- 
tion been  disclosed. 


MONTEREY    COUNTY.  123 

MONTEREY  COUNTY. 

Cholame  Parkfield  Mine. — In  Sec.  35,  T.  22  S.,  R.  14  E.,  and 
Sec.  2,  T.  23  S.,  R.  14  E.;  6  miles  from  Parkfield,  and  32  miles 
from  the  railroad  at  San  Miguel.  Owners,  L.  S.  Patriquin, 
G.  W.  Ford,  and  G.  W.  B.  Anderson,  of  Parkfield,  ^lonterey 
County.  This  property  consists  of  three  claims,  covering  4500 
feet  by  600  feet  in  width,  in  a  course  X.  60°  W.,  following  as 
closely  as  possible  a  contact  of  serpentine  and  highly  meta- 
morphosed rocks  of  the  Franciscan  series.  The  outcrop  of 
these  metamorphics  is  not  ver>^  large.  At  both  ends  of  the 
property  the  surface  is  entirely  in  serpentine,  which  formation 
forms  the  prominent  surface  rock  of  the  vicinity  abutting 
against  the  Chico  sandstone.  It  is  highly  silicified,  and  in 
many  cases  only  a  surface  flow;  fiequently  small  areas  of 
Franciscan  sandstone  crop  through  the  serpentine,  while  in 
the  gulches  evidence  can  be  found  that  shales  underlie  the 
serpentine.  The  contact  crosses  a  side  ridge  of  the  main 
mountain  range  and  the  outcrop  of  the  metamorphic  rocks 
covers  the  apex  of  this  ridge.  The  contact  has  been  reached 
by  two  tunnels  starting  respectively  from  the  southwest  and 
the  northeast  side  of  the  ridge,  both  at  about  the  same  level, 
350  feet  below  the  highest  point.  The  tunnel  from  the  south- 
west has  just  reached  the  contact  at  a  distance  of  964  feet  from 
its  mouth,  showing  some  cinnabar  at  the  contact.  The  tunnel 
from  the  northeast  reaches  the  same  contact  330  feet  from  the 
mouth,  and  has  been  driven  about  500  feet  northwesterly  along 
the  contact,  showing  some  ore  in  several  places.  The  line  of 
contact  is  very  irregular,  generally  without  any  gouge,  but 
where  there  is  any  gouge,  the  slickensides  show  movements  in 
various  directions,  vertical  and  horizontal.  The  sandstone  is 
verj'  much  fractured  and  has  been  recemented  by  quartz,  calcite, 
and  gypsum.  Part  of  the  serpentine  has  been  highly  silicified, 
altered  into  a  chalcedonic  material.  The  cinnabar  forms 
principally  in  the  fractured  sandstone,  but  also  occasionally  in 
the  serpentine  close  to  the  contact.  The  tunnel  from  the  south- 
west side  demonstrates  that  the  cinnabar  deposition  in  the 
altered  Franciscan  sandstones  is  by  no  means  restricted  to  the 
contact.  Several  large  ore  pockets  have  been  found  in  this 
tunnel  over  400  feet  from  the  contact,  and  about  100  feet  there- 
from a  peculiar  deposit  carr>-ing  a  very  high  percentage  of  free 


121  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

sulphur,  through  which  cinnabar  is  disseminated,  -was  cut  and 
followed  for  a  few  feet.  The  metamorphic  rocks  are  very- 
much  shattered;  large  crevices,  probably  resulting  from  earth- 
quakes, are  frequently  found.  The  entire  formation  has  an 
ochery  character  from  oxidized  iron  sulphides,  and  in  several 
places  can  be  seen  the  effects  of  the  high  heat  resulting  from 
the  oxidation  of  these  sulphides.  There  are  several  surface 
cuts  wherein  good  ore  has  been  found  on  the  contact.  The 
richest  surface  deposit,  carrying  exceedingly  rich  ore  in  altered 
sandstone,  is  cut  off  by  a  body  of  serpentine.  A  tunnel  run  50 
feet  below  this  deposit  shows  a  most  irregular  formation — flint, 
serpentine,  then  a  broken  mass  of  bowlders  of  flint  and  meta- 
morphosed sandstone  mixed  with  clay,  then  again  serpentine, 
but  no  signs  of  ore.  This  rich  surface  deposit,  showing  seams 
of  nearly  pure  cinnabar  and  metacinnabarite  in  fracture  planes 
of  flinty  rock,  is  clearly  not  in  place,  but  from  where  it  has 
moved  to  its  present  position  is  as  yet  an  open  question.  The 
neighborhood  is  very  sparsely  timbered,  both  in  regard  to 
mining  timber  and  for  fuel  purposes. 

Dutro  Mine. — This  is  in  the  San  Carpojo  district,  in  the  south- 
west corner  of  Monterey  County,  two  miles  in  an  air  line  from 
the  ocean,  at  the  head  of  the  west  fork  of  San  Carpojo  Creek, 
in  the  S.W.  %  of  the  S.E.  %  of  Sec.  28,  T.  24  S.,  R.  6  E. 
Owner,  Frank  Dutro  Martinez,  Santa  Maria,  Santa  Barbara 
County;  G.  E.  Van  Gordon,  of  Cambria,  San  Luis  Obispo 
County,  lessee.  This  property  is  situated  on  a  line  of  croppings 
running  nearly  east  and  west,  in  silicified  Franciscan  sand- 
stone. As  far  as  can  be  judged  the  ledge  has  a  southern  dip. 
On  the  property  is  a  shaft  which  is  claimed  to  be  100  feet  deep 
and  a  drift  about  40  feet  on  the  ledge.  These  works  are  caved 
in.  Judging  from  the  material  on  the  dump  the  ledge  matter 
is  of  a  flinty  character,  carrjdng  sensible  amounts  of  cinnabar. 
The  vicinity  is  well  watered  and  timbered. 

Table  Mountain  Quicksilver  Mine. — This  property  is  12  miles 
from  Parkfield,  and  38  miles  from  the  railroad  at  San  Miguel; 
in  Sec.  30,  T.  23  S.,  R.  15  E.  Owner,  G.  W.  White,  of  Park- 
field,  Monterey  County.  This  mine  is  located  on  top  of  Table 
Mountain.  The  surface  is  nearly  exclusivel}-  serpentine.  The 
works  are  located  nearly  in  the  center  of  the  claim;  the  lowest 
tunnel  at  about  100  feet  below  the  top  of  the  mountain.  At 
present  only  one  tunnel,  50  feet  long,  in  decomposed  serpentine, 


SAN    BENITO    COUNTY.  125 

course  X.  60"  E.,  is  accessible.  On  the  left  side  it  shows,  over  a 
distance  of  30  feet,  a  seam  carrying  cinnabar,  slightly  dipping  to 
the  northwest.  In  the  decomposed  serpentine  are  found  bowl- 
ders of  flinty  quartz  carrying  some  cinnabar,  but  no  permanent 
formation  has  as  yet  been  reached.  At  the  southeast  end  of  the 
claim  a  shaft  10  feet  deep  has  been  sunk  on  a  chalcedonic 
material  showing  some  cinnabar.  Between  these  two  work- 
ings a  tunnel  has  been  started,  course  N.  40°  E.,  in  shale,  130 
feet  long,  the  breast  being  in  decomposed  serpentine.  Below 
the  entrance  of  this  tunnel  the  Chico  sandstone  is  found  abut- 
ting against  the  serpentine.  No  ore  has  as  yet  been  found  in 
this  tunnel. 

SAN  BENITO  COUNTY. 

San  Benito  Count}'  is  traversed  by  two  parallel  mountain 
ranges,  the  Gabilan  and  the  Mount  Diablo,  which  unite  south  of 
the  county  in  Monterey  County.  Only  in  the  latter — the  eastern 
range — have  quicksilver  deposits  of  any  consequence  as  yet 
been  developed.  The^-  may  be  segregated  into  three  districts: 
The  New  Idria  district,  in  the  southeastern  part  of  the  county ; 
the  Stayton  district,  in  the  extreme  northeastern  corner,  taking 
in  small  portions  of  Merced  and  Santa  Clara  counties;  and  a 
third  district,  situated  nearly  in  the  center  of  the  county  in 
the  mountain  cluster  between  San  Benito  creek  on  the  west 
and  Tres  Pinos  and  Panoche  creeks  on  the  east,  which  might 
properly  be  called  the  Central  San  Benito  district.  The 
geology  of  the  districts  will  be  treated  separately.  [See,  also. 
Report  State  Mining  Bureau  of  Cal.,  XI,  page  370.]  They 
are  not  referred  to  in  geographical  sequence,  owing  to  the 
alphabetical  arrangement  of  the  respective  mines  in  this 
bulletin. 

Central  San  Benito  District. — This  district  contains  only  a  few 
scattered  mines  on  which  development  work  has  been  per- 
formed. It  is  located  in  the  Mount  Diablo  range,  which  con- 
sists mainly  of  rocks  of  the  Franciscan  series,  in  places 
covered  by  or  adjacent  to  younger  formations.  Its  geological 
features  are  mentioned  in  the  descriptions  of  the  Bradford  and 
Cerro  Bonito  mines,  the  two  principal  mines  of  the  district.  The 
country-  is  well  timbered,  both  for  mining  and  fuel  purposes. 
The  railroad  outlet  is  at  Tres  Pinos. 

New  Idria  District. — The  New  Idria,  San  Carlos,  Sulphur 
Spring,  and  Molina  mines  in  this  district  were  discovered  in  the 


126  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

early  5o"s  by  miners  who  had  worked  near  the  present  site  of 
the  Aurora  mine  on  what  was  at  first  supposed  to  be  a  silver 
mine,  but  which  proved  to  be  a  deposit  of  chrome  iron. 

The  geological  map  of  the  quicksilver  district  in  the  southern 
portion  of  San  Benito  County  shows  that  this  district  contains 
a  belt  of  metamorphic  rocks  having  a  general  northwest  strike, 
bounded  on  both  sides  by  Chico  formations,  and  consisting  of 
a  belt  of  serpentine  in  the  center,  having  to  the  northeast  a 
rather  narrow  belt  of  metamorphic  rocks,  mainly  sandstone, 
and  to  the  southeast  a  much  wider  belt  of  metamorphic  rocks, 
containing,  however,  much  more  slate.  The  main  deposits  of 
quicksilver  ores  are  located  very  close  to  the  contact  of  the 
serpentine  with  these  sandstones  and  shales.  They  form  tw^o 
parallel  lines,  one  comprising  the  San  Carlos,  Aurora,  and  New 
Idria  mines,  and  the  other  the  Picachos,  Andy  Johnson,  and 
Clear  Creek  mines.  The  Don  Juan  and  Don  Miguel  mines  are 
outside  of  this  contact  belt,  entirely  in  the  metamorphic  shales 
and  sandstones. 

The  mineralized  deposits  at  New  Idria  are  situated  on  a  line 
having  a  general  northwestern  trend.  Between  the  New  Idria 
and  San  Carlos  deposits,  which  are  extensively  developed,  are 
the  Sulphur  Spring  and  Molina  mines,  the  former  being  the 
only  one  found  immediately  in  contact  with  the  serpentine  on 
this  line.  The  country'  rock  of  the  New  Idria  and  the  San 
Carlos  is  ver>'  similar;  the  rocks  found  in  the  lower  tunnel  of 
the  San  Carlos  are  strikingly  similar  to  those  found  in  the  New 
Idria  mine.  The  geological  map  of  this  section  indicates  that 
the  high  peaks  of  the  New  Idria  and  San  Carlos  are  formed  of 
sandstones  and  shales,  while  surrounded  by  serpentine.  This 
serpentine  is  generally  a  hard,  light-colored  variety,  only  occa- 
sionally changed  by  silicification  into  black  opaline  rock.  West 
of  San  Carlos  Peak  is  the  Aurora  mine,  entirely  surrounded  by 
serpentine. 

Close  to  the  metamorphic  series  the  Chico  is  sensibly  dis- 
turbed, but  only  for  a  belt  not  over  looo  feet  wide,  past  which 
the  Chico  beds  of  drab-colored  sandstone  can  be  seen  outcrop- 
ping very  regularl}'  at  the  surface. 

The  serpentine  is  by  far  the  prevailing  rock  of  the  meta- 
morphic series.  There  are  indications  that  in  places  the  ser- 
pentine appearing  at  the  surface  is  only  a  surface  occurrence 
and  does  not  persist  in  depth,  as  will  be  seen  later  herein,  and 
also  in  the  description  of  the  Mexican  mine,  Fresno  County, 


/A^tHH  Si  ^ 


SAN    BENITO    COUNTY. 


127 


situated  on  the  northeastern  contact  of  the  same  belt  of  the 
metamorphic  series.  The  serpentinization  of  the  rock  is  very 
irregular,  and  sometimes  very  light,  while  in  other  places  the 
rock  is  a  talcose,  bluish-green  serpentine,  with  a  more  or  less 
conchoidal  fracture.  Inclusions  of  bodies  of  sandstone  and 
shale  are  found  in  the  serpentine.  On  a  ridge  over  a  mile  long, 
having  a  course  about  S.  30°  W.,  running  from  the  divide  south 
of  the  San  Carlos,  along  the  headwaters  of  Clear  Creek  toward 
the  Picachos,  and  at  the  surface  entirely  formed  of  serpentine, 
all  gradations  from  sandstone  to  serpentine  are  found.  In  one 
inclusion  of  a  yellow  sandstone,  at  least  100  feet  by  50  feet  at 
the  surface,  seams  of  serpentine  over  a  fourth  of  an  inch  wide 
cutting  through 
the  sandstone  can 
be  seen.  The  ac- 
companying pho- 
tograph (No.  11) 
of  a  thin  section 
(enlarged)  con- 
clusively proves 
the  serpentiniza- 
tion of  the  sand- 
stone. In  the  belt 
between  the  ser- 
pentine and  the 
Chico,  a  great  part 
of  the  sandstone 
is  so  thoroughly 
recrystallized  by 
metamorphic  ac- 
tion that  it  is  very 
difficult  to  decide  in  the  field  whether  the  material  is  meta- 
morphic sedimentary^  or  eruptive. 

In  the  lower  part  of  Clear  Creek  near  its  entrance  into  the 
San  Benito,  a  conglomerate  is  found  on  the  hills,  containing 
pebbles  of  all  kinds  of  rocks,  including  serpentine.  This 
region  must  have  been  a  lake  of  large  dimensions,  as  conglom- 
erate is  found  1 100  feet  above  the  level  of  Hernandez.  Another 
appearance  of  conglomerate  is  found  overlying  metamorphic 
sandstones  and  shales,  at  an  elevation  of  4700  feet  (2150  feet 
above  Hernandez),  forming  the  highest  point  of  the  mountain 
cluster,  which  forms  the  big  bend  of  San  Benito  Creek,  south 
of  the  Picachos  (Dominic  Peak). 


PHOTO  No.  n.    Thin  Section  of  Sandstone  and 

Serpentine  from  Xew  Idria  District. 

41  Diameters. 


*i>llciili  .ilcyivJijy 


t:  ^A/. 

n 


t  '  ■ 

I 


r  jh  cr  o  af  "y 


T 
1 


SAN    BENITO    COUNTY. 


127 


situated  on  the  northeastern  contact  of  the  same  belt  of  the 
metamorphic  series.  The  serpentinization  of  the  rock  is  very 
irregular,  and  sometimes  very  light,  ^vhile  in  other  places  the 
rock  is  a  talcose,  bluish-green  serpentine,  with  a  more  or  less 
conchoidal  fracture.  Inclusions  of  bodies  of  sandstone  and 
shale  are  found  in  the  serpentine.  On  a  ridge  over  a  mile  long, 
having  a  course  about  S.  30°  W.,  running  from  the  divide  south 
of  the  San  Carlos,  along  the  headwaters  of  Clear  Creek  toward 
the  Picachos,  and  at  the  surface  entirely  formed  of  serpentine, 
all  gradations  from  sandstone  to  serpentine  are  found.  In  one 
inclusion  of  a  yellow  sandstone,  at  least  100  feet  b}'  50  feet  at 
the  surface,  seams  of  serpentine  over  a  fourth  of  an  inch  wide 
cutting  through 
the  sandstone  can 
be  seen.  The  ac- 
companj'ing  pho- 
tograph (Xo.  11) 
of  a  thin  section 
(enlarged)  con- 
clusively proves 
the  serpentiniza- 
tion of  the  sand- 
stone. In  the  belt 
between  the  ser- 
pentine and  the 
Chico,  a  great  part 
of  the  sandstone 
is  so  thoroughly 
recrystallized  by 
metamorphic  ac- 
tion that  it  is  very 
difficult  to  decide  in  the  field  whether  the  material  is  meta- 
morphic sedimentary  or  eruptive. 

In  the  lower  part  of  Clear  Creek  near  its  entrance  into  the 
San  Benito,  a  conglomerate  is  found  on  the  hills,  containing 
pebbles  of  all  kinds  of  rocks,  including  serpentine.  This 
region  must  have  been  a  lake  of  large  dimensions,  as  conglom- 
erate is  found  1 100  feet  above  the  level  of  Hernandez.  Another 
appearance  of  conglomerate  is  found  overlying  metamorphic 
sandstones  and  shales,  at  an  elevation  of  4700  feet  (2150  feet 
above  Hernandez),  forming  the  highest  point  of  the  mountain 
cluster,  which  forms  the  big  bend  of  San  Benito  Creek,  south 
of  the  Picachos  (Dominic  Peak). 


PHOTO  No.  11.    Thin  Section  of  Sandstone  and 

Serpentine  from  New  Idria  District. 

41  Diameters. 


12S  QUICKSILVER    RESOUKCES    OF    CALIFORNIA. 

Along  the  lower  course  of  Clear  Creek  and  its  drainage 
serpentine  and  metamorphic  sandstones  are  very  intricately 
mixed.  For  a  considerable  distance  the  creek  and  its  tributa- 
ries have  cut  their  beds  in  the  serpentine,  while  above  on  the 
ridges  sandstone  is  extensively  represented,  indicating  that 
the  serpentine  underlies  the  sandstone,  which  latter  is  generally 
strongly  silicified.  The  serpentine  itself  is  generally  silicified 
to  a  certain  extent,  and  the  entire  formation,  at  the  surface 
where  the  serpentine  shows,  looks  as  though  the  sandstone 
has  been  eroded.  Part  of  the  serpentine  is  denuded  of  vege- 
tation, and  the  material  has  deteriorated  into  a  granular 
mass ;  but  a  great  portion  of  the  serpentine  territory  is  covered 
with  brush.  In  some  places  in  the  region  between  Clear  Creek 
and  San  Benito  Creek,  the  barren  serpentine  is  capped  by  a  few 
feet  of  ferruginous  chert,  containing  so  much  iron  that  the 
entire  rock  has  a  brownish-red  color.  These  patches  are 
covered  with  brush,  and  as  the  soil  in  the  part  of  the  serpentine 
belt  covered  with  brush  has  a  much  darker  appearance  than 
that  of  the  barren  ground,  which  is  light  yellow  to  white,  it 
must  be  supposed  that  the  iron  contents  of  the  serpentine  have 
a  certain  influence  on  the  growth  of  brush.  Whether  the  iron 
content  is  due  to  the  character  of  the  rock  which  has  been 
serpentinized  is  as  yet  an  open  question. 

The  schists  of  the  older  series  are  found  in  a  few  places — in 
the  bottom  of  Clear  Creek  Caiion  just  above  and  below  the 
Clear  Creek  mine,  and  in  San  Benito  Creek,  near  the  south- 
east corner  of  Sec.  22,  T.  i8  S.,  R.  II  E.  In  Clear  Creek  Canon 
the  schists  underlie  the  serpentine,  and  are  partly  ver3^  much 
distorted,  but  their  strike  is  about  N.  45°  E.,  dip  nearly  verti- 
cal southeast.  In  San  Benito  Cafion  they  are  exposed  on  the 
east  side  of  the  creek,  the  opposite  side  being  formed  of  thinly 
bedded  shales,  probabh-  belonging  to  the  Chico,  having  a  south- 
east strike  and  a  southwest  dip.  The  schists  are  not  very 
wide,  and  are  inclosed  in  sandstones.  Another  small  cropping 
of  schist  is  found  a  little  higher  up  the  creek  at  the  New  York 
mine. 

In  San  Benito  Canon,  near  the  Don  Juan  mine,  the  non- 
conformity of  the  metamorphic  series,  with  a  strike  nearly  east 
and  west  and  a  dip  south,  and  the  Chico  on  the  other  side  of 
the  creek,  with  a  strike  S.  45°-6o°  E.,  dip  southwest,  is  strik- 
ingly illustrated.  Going  up  the  canon  above  the  old  retort  of 
the  Don  Juan  mine  the  metamorphic  shales  can  be  seen  under- 


I  I  Serpenlirg 

I  I  /ie/omorp/>. 

\  I  Aoi^  Igneous 

t  i  Bos/c  /gneous 


Geolojo'  l>y  Wi".  Korstiier,  E.M. 

Geological  Map  of  Stayton  Mining  District. 

Issued  by  the  California  State  Mining  Bureau— Lewis  E.  Aubury.  State  Mineralogist,  1903. 


SAN    BENITO    COUNTY.  129 

lying  the  sandstones,  which  form  nearly  the  entire  surface  of 
Dominic  Peak,  the  mountain  between  the  elbow  of  San  Benito 
and  Picachos  creeks,  except  at  its  highest  point  (4720  feet), 
1900  feet  above  the  creek,  which  is  covered  by  a  conglomerate, 
traces  of  which  can  be  found  nowhere  on  the  mountain  side. 
Part  of  the  sandstone  is  only  slightly  silicified,  principally  by 
quartz  seams  in  the  fractures;  but  on  the  southern  part  of  the 
top  of  this  hill,  jasper  is  found  in  sensible  quantity,  while  this 
formation  is  rare  on  the  hillsides.  The  sandstones  are  non- 
conformable  with  the  underlying  shales.  The  chert  beds  are 
almost  entirely  absent  in  this  region.  Only  one  very  small 
exposure  in  the  lower  part  of  Clear  Creek  has  been  observed, 
which  contains  a  great  amount  of  iron  oxide.  Jasper  is  also 
but  slightly  represented.  In  fact  the  silicification  process  has 
not  been  so  intense  in  this  region  as  in  other  parts  of  the 
quicksilver  belt.  The  question  might  arise  whether  this 
phenomenon  has  any  connection  with  the  small  representation 
of  igneous  rocks  and  the  absence  of  mineral  springs  in  this 
region.  The  small  extent  of  the  later  opalizing  silicification  is 
also  to  be  noted,  no  belts  of  opaline  rock  being  found  in  close 
proximity  to  the  ore  deposits,  while  such  rocks  are  found  to 
some  extent  in  the  mass  of  serpentine. 

The  district  is  from  60  to  70  miles  distant  from  the  railroad 
at  Tres  Pinos,  San  Benito  County,  with  which  it  is  connected 
by  two  good  roads  from  New  Idria  via  Vallecitos  Canon,  and 
from  Hernandez  down  San  Benito  Creek. 

The  supply  of  timber  is  rather  scarce.  The  price  of  cord- 
wood  is  from  $5  to  $6.50  per  cord;  round  mining  timber,  11 
inches  at  the  small  end,  costs  12  cents  and  over  per  linear  foot; 
square  timber,  including  freight  from  railroad  ($12  to  ^18  per 
ton),  costs  $40  and  over  per  1000  feet  (B.  M.). 

Stayton  District. — This  district  is  situated  in  the  corner  of 
San  Benito,  Merced,  and  Santa  Clara  counties,  and  comprises 
parts  of  these  three  counties,  but  being  principally  in  San 
Benito  County  is  included  within  the  latter.  [See  geological 
map  of  the  Stayton  District.] 

The  surface  rock  of  this  district  is  prominently  of  igneous 
origin  and  except  in  the  northwestern  part  the  underlying 
sedimentaries  are  almost  exclusively  found  in  the  bottoms  of 
the  deeply -eroded  gulches.  The  post-Tertiary  igneous  rocks 
vary  greatly  in  character;  from  very  fine-grained,  dark-colored 
basic,  basaltic  rocks,  to  very  fine-grained,  hard,  nearly  white 

9— QR 


130  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

acidic  rocks.  The  great  majority  is,  however,  a  light  grayish- 
colored  porphj^ritic  rock,  which  Whitney  [see  Geology  of  Cali- 
fornia, page  46]  classified  as  trachyte,  but  which  closely 
answers  the  asperites  described  by  Becker.  [See  Mon.  XIII, 
page  151.]  There  is  no  doubt  that  this  district  has  been  the 
locus  of  repeated  igneous  eruptions,  and  that  these  different 
igneous  rocks  represent  various  stages  of  magmatic  differentia- 
tion. [See  Prof.  \V.  Brogger,  Q.  J.  of  the  Geol.  Society, 
vol.  L,  page  29,  and  vol.  LII,  page  607  and  following;  J.  P.  Idd- 
ings,  ibid.,  page  609,  and  Bull.  Phil.  Soc.  of  Wash.,  vol.  XII, 
page  151.] 

The  sedimentar\'  rocks  belong  to  the  metamorphic  series, 
prominently  sandstones.  At  one  place  at  the  northwest  foot 
of  Mariposa  Peak,  a  small  exposure  of  chert  was  found. 
Some  shales  are  also  exposed,  and  at  one  place  in  I,os  Banos 
Creek,  at  the  foot  of  the  grade  of  the  road  from  Staj'ton  to 
lyOS  Banos,  a  fine  compact  conglomerate  is  found  which  may 
probabl}'  represent  the  conglomerate  forming  the  basal  mem- 
ber of  the  metamorphic  series,  as  described  by  Fairbanks. 
[See  Bull.  Geol.  Soc.  of  America,  vol.  VI.]  This  conglomer- 
ate must  not  be  confounded  with  the  coarse  conglomerate 
forming  at  present  in  the  beds  of  some  creeks.  Only  at  one 
place  in  the  northwest  corner  of  the  district,  in  the  old  Com- 
stock  property,  is  an  exposure  of  serpentine  noted,  and  this 
not  over  1000  feet  wide,  abutting  to  the  w^est  against  schist 
and  to  the  east  against  a  flow  of  basalt. 

There  are  no  hot  springs  in  the  district,  but  in  the  western 
belt,  sulphur  emanations,  principally  carrying  antimonious  ores, 
are  very  prominent,  and  the  ledge  matter  and  part  of  the  wall 
rocks  in  all  the  metalliferous  deposits  have  been  so  thoroughh- 
leached  by  sulphurous  waters  that  the  determination  of  their 
original  composition  is  extremel}^  difficult,  if  not  impossible. 

The  ore  deposition  is  undoubtedly  posterior  to  the  eruption 
and  consolidation  of  the  volcanic  rocks.  At  one  place  in  the 
Staj-ton  mine,  cinnabar  can  be  found  replacing  some  leached 
minerals  in  the  igneous  rocks. 

The  district  is  about  16  miles  from  the  railroad  at  Hollister, 
San  Benito  County.  The  vicinity  is  practically  void  of  mining 
timber,  but  there  is  ample  fuel  timber  at  $3  per  cord. 

The  following  claims  as  nvimbered  on  the  map  are  in  this 
district:  i.  Santa  Cruz;  2.  Mariposa;  3.  Green  Valley;  4.  F, 
Smith;    5.  Cold  Spring;    6.  McLeod;    7.  Badger;    8.  Fairplay; 


SAN    BENITO   COUNTY.  131 

9.  Santa  Clara;   10.  Pacific;   11.  Last  Chance;   12.  North  Star; 
13.  Stayton. 

Andy  Johnson  Mine. — New  Idria  District,  in  Sec.  13,  T.  18  S., 
R.  11  E.,  and  Sec.  18,  T.  18  S.,  R.  12  E.  Thomas  Flint,  owner, 
Hollister.  This  mine  is  located  on  the  line  of  croppings  men 
tioned  in  the  general  description  of  the  district,  running  from 
the  Picachos  to  the  Clear  Creek  mine.  All  the  old  works  are 
inaccessible. 

Aurora  Mine  ( formerly  Morning  Star ) . — New  Idria  District.  In 
Sec.  5,  T.  18  S.,  R.  12  E.  Owners,  A.  Leonard,  San  Benito; 
Thomas  Flint,  Hollister;  Estate  of  Ig.  Ceseiio;  S.  E.  Sadler, 
No.  34  Steuart  street,  San  Francisco;  bonded  to  the  Aurora 
Quicksilver  Mining  Company,  B.  J.  Potter,  president.  No.  165 
East  Twelfth  street,  Oakland.  Contains  eight  claims,  the 
Aurora,  Leonard,  Molly  O,  Morgan,  Aurora  Extension,  Morn- 
ing Star,  Sadler,  and  Traction.  This  property  was  discovered 
in  1853  and  efforts  have  been  made  at  different  times  to  pros- 
pect it.  The  property  is  located  on  a  line  of  croppings  having 
a  course  S.  15°  E.,  situated  south  of  San  Carlos  Creek  at  the 
foot  of  San  Carlos  Peak,  and  running  up  about  half  wa)^  to 
the  top  of  the  divide  between  San  Carlos  and  Clear  creeks. 
These  croppings  are  about  600  feet  long  and  from  50  to  100 
feet  wide.  Their  course  prolonged  to  the  northwest  would 
come  very  close  to  the  New  Idria  mine.  They  are  entirely 
surrounded  by  serpentine,  and  no  other  rock  is  found  at  the 
surface;  neither  do  the  short  tunnels  and  shallow  open  cuts  on 
the  mine  show  any  other  material.  The  upper  tunnel,  10  feet 
long,  is  275  feet  above  the  furnace.  Another  tunnel,  25  feet 
long,  near  the  bed  of  the  creek,  is  25  feet  above  the  same  level. 
Both  show  only  serpentine.  There  is  a  large  open  cut  on  the 
hillside  in  the  croppings,  from  which  some  ore  has  been  taken. 
Above  the  latter  is  an  open  cut,  200  feet  above  the  furnace 
level,  which  is  about  100  feet  long  and  30  feet  high.  The 
course  of  its  face  is  about  northeast.  In  the  northeastern  half, 
a  horizontal  stratum  of  opalized  serpentine  3  feet  wide  and 
carrying  seams  of  cinnabar  is  found.  This  property  is  equipped 
with  a  two-chamber  Fitzgerald  furnace. 

Bradford  Mine  (formerly  Cerro  Gordo). — Central  San  Benito 
District.  In  Sees.  3,  4,  and  9,  T.  15  S.,  R.  8  E.  Owner,  H.  R. 
Bradford,  No.  7  North  Market  street,  San  Jose.  This  mine  lies 
on  Tres  Pinos  Creek.  The  drainage  of  this  creek  is,  up  to 
about  one  mile  below  the  mine,  in  gravel  beds  lying  nearly 


132 


QUICKSILVER    RESOURCES   OF    CALIFORNIA. 


horizontal.  At  Johnson's  place,  sandstone  appears  on  the 
south  side  of  the  creek,  in  narrow  beds  standing  nearly  vertical. 
The  sandstone  belt  runs  along  the  west  side  of  the  propert}-;  to 
the  east  lies  a  wide  belt  of  serpentine.  Both  the  sandstone  and 
the  serpentine  have  a  northwesterly  strike.  The  serpentine 
as  found  in  the  mine  workings  dips  northeast.     [See  Fig.  45.] 

Elev.of  collar    2280 


Section 


Tunnel 


jnclmedShoH 


plan 


Fig.  45.    Workings.  Bradford  Mine. 

The  western  part  of  the  serpentine  consists  of  a  highh-  silicified 
belt  of  varying  width,  in  part  opaline  rock,  carn.-ing  some 
cinnabar.  Between  this  belt  and  the  sandstone  is  a  wide  belt 
of  black  gouge,  and  at  least  one  other  belt  of  black  gouge  has 
been  found  in  tunnel  No.  2  in  the  silicified  serpentine.  The 
width  of  the  contact  gouge  between  the  sandstone  and  the 
overlying  serpentine  is  not  known,  but  from  surface  indications 


SAN    BENITO    COUNTY.  133 

it  must  be  rather  wide.  Where  crosscut  at  the  bottom  of  the 
shaft  [see  Fig.  45] ,  the  opalized  serpentine  between  the  gouges 
is  only  16  feet  wide.  The  next  gouge  is  at  that  place  160  feet 
wide.  This  opalized  serpentine  crops  out  in  a  northwestern 
direction  past  the  boundar}'  of  the  property,  and  north  of  the 
creek.  It  carries  some  cinnabar,  but  as  yet  no  body  of  work- 
able ore  has  been  found. 

The  incline  shaft,  following  the  contact  of  the  opalized  ser- 
pentine with  the  underlying  gouge,  has  been  sunk  200  feet  on 
the  incline.  A  tunnel  has  been  run  160  feet  vertically  below 
the  collar  of  this  shaft;  it  is  535  feet  long,  and  reaches  under 
the  shaft,  but  follows  the  contact  of  the  opalized  serpentine 
and  the  overlying  gouge.  No  ore  bodies  have  been  disclosed 
by  this  work;  however,  the  serpentine  carries  some  cinnabar 
throughout. 

The  surrounding  country  is  well  timbered.  The  mine  is  18 
miles  from  Tres  Pinos  railroad  station,  connected  by  a  good 
wagon  road.  The  existence  of  cinnabar  in  the  locality  was 
discovered  in  1859  as  an  incident  of  the  work  of  constructing 
a  wagon  road  by  the  New  Idria  Mining  Company,  and  much 
effort  by  various  parties  has  since  been  expended  in  the  pros- 
pecting and  development  of  the  early  find. 

Butts  Mine. — Central  San  Benito  District.  In  Sec.  4,  T.  16  S., 
R.  8  E.  Wm.  Butts,  of  Pine  Rock,  San  Benito  County,  owner. 
The  country  rock  is  a  coarse  sandstone,  through  which  cuts  a 
ledge  having  a  course  nearly  southwest,  dipping  north  about 
50°,  wherein  some  sandstone  occurs;  seams  of  silica  fill  the 
fractures  of  the  sandstone,  and  carry  a  great  amount  of  iron 
oxides.  The  formation  in  the  neighborhood  of  this  ledge  is 
very  irregular;  shales,  chert,  and  some  serpentine  are  found  all 
intricatel}'  mixed  up.  Except  near  the  croppings  of  the  ledge 
no  workable  ores  have  as  yet  been  found.  A  tunnel  300  feet 
long  has  been  run,  and  a  shallow  shaft  about  20  feet  deep  has  been 
sunk.  The  property  is  equipped  with  a  2  Q  retort  furnace. 
The  neighborhood  of  the  property  contains  some  fuel  timber, 
but  little  mining  timber.  The  distance  from  Tres  Pinos  rail- 
road station  is  21  miles  by  a  good  wagon  road. 

Cannon  Mine. — Central  San  Benito  District.  In  Sec.  4,  T.  15  S., 
R.  8  W.  A.  C.  Cannon,  of  Emmett,  San  Benito  County, 
owner.    This  property  lies  adjacent  to  and  north  of  the  Bradford, 


184 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


on  the  same  croppings.  A  drift  130  feet  long  has  been  run, 
with  a  winze  30  feet  deep  in  the  silicified  serpentine.  At  the 
bottom  of  the  winze  is  a  drift  90  feet  long,  showing  that  the 
serpentine  carries  some  cinnabar,  but  without  disclosing  a  pay 
shoot. 


T15S.  EWE. 


CERRO  BENITO  MINE 


Cerro  Bonito  Mine. — Central  San  Benito  District.  In  Sec.  31, 
T.  15  S.,  R.  10  E.,  and  Sec.  6,  T.  16  S.,  R.  10  E.  Cerro  Bonito 
Quicksilver  Company,  owner;  H.  R.  Bradford,  No.  7  North 
Market  street,  San  Jose,  general  manager;  James  Tread- 
well,  San  Francisco,  president;  S.  T.  Kennedy,  Llanada,  San 
Benito  County,  superintendent.     This  mine  was  opened  about 


SAN    BENITO    COUNTY.  135 

1874  and  worked  by  the  old  Cerro  Bonito  Company  until  1876. 
It  is  stated  that  the  mine  has  produced  about  800  flasks. 

The  present  company,  organized  September,  1902,  has  been 
working  this  property  since  then,  and  is  at  present  reopening 
the  main  tunnel.  This  work  has  proceeded  to  a  length  of 
650  feet,  the  entire  length  of  the  tunnel  being  930  feet.  This 
tunnel,  as  far  as  opened,  is  in  the  black  gouge  mixed  with 
some  sandstone;  from  a  shoot  connecting  with  the  old  upper 
works,  some  jaspery  material  has  come  down,  showing  some 
cinnabar.  The  companj^  is  also  refitting  the  old  25-ton  coarse- 
ore  furnace.  The  old  workings  consist  of  a  great  amount  of 
surface  work  and  numerous  underground  works,  which  are 
largely  inaccessible;  but  those  which  can  be  entered  show 
development  to  have  been  very  extensive.  Up  to  the  present 
time  the  company  has  not  reopened  any  large  ore  bodies. 

The  entire  geology  of  the  neighborhood  is  verj^  complicated, 
and  from  what  is  disclosed  in  the  works  that  can  be  entered, 
no  sufficient  data  can  be  collected  to  give  a  satisfactory^  and 
clear  description  of  the  geology.  Between  the  property  and 
Panoche  Valley  is  a  flow  of  basalt — probably  a  surface  flow. 
This  appears,  judged  from  surface  indications,  to  be  the  only 
igneous  rock  in  the  vicinity.  The  top  of  Cerro  Bonito  Hill, 
which  rises  steeply,  is  surrounded  by  two  lines  of  bluffs  [see 
map  of  the  Cerro  Bonito  mine] ,  one  forming  the  top  itself,  the 
other  from  200  to  300  feet  lower  and  much  more  prominent, 
especially  on  the  north  and  northwest  sides,  where  in  places  the 
bluffs  are  100  feet  high.  These  bluffs  are  formed  of  a  hard  silice- 
ous material,  most  probably  a  metamorphic  breccia  recemented 
by  silicification.  Some  black  opaline  rock  is  found  through  this 
rock,  and  occasionally  some  sandstone.  The  true  relation 
between  this  breccia  and  the  bedded  sandstone  can  not  be 
traced  from  the  present  accessible  development  works.  In 
three  places  the  breccia  overlies  the  regularly  bedded  sand- 
stone. Going  northwest  from  the  southern  part  of  the  prop- 
erty these  places  are: 

First — Sandstone  tunnel  (^)  [see  map],  an  extensive  and 
intricate  network  of  underground  drifts,  winzes,  and  shafts,  in 
sandstone.  At  their  western  end  a  gouge  is  found  dipping 
from  10°  to  15°  in  a  westerly  direction  and  carrying  some  ser- 
pentine coming  in  from  the  roof  and  overlying  the  sandstone 
which  lies  in  nearly  horizontal  regular  beds,  especially  in  the 


136  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

western  part  of  the  works;  near  the  mouth  of  the  works  some 
nearly  vertical  narrow  seams  of  quartz  cut  through  the  sand- 
stone. 

Second — Farther  northwest  is  an  open  cut  (/),  from  which 
extensive  works  run  into  the  hill.  In  one  of  these  the  breccia 
is  found  overlying  the  sandstone,  dipping  about  30*^  N.,  40^^  E. 
This  breccia  is  found  continuous  to  the  old  open  cut  works  and 
carries  cinnabar  all  through,  overl3dng  a  stratum  of  serpentine. 
Third — Northeast  of  this  work  is  a  long  tunnel  {h)  running 
in  a  southwesterl}'  direction.  In  this  tunnel  sandstone  is  found 
underlying  the  breccia,  which  is  for  long  distances  replaced  by 
black  gouge.  Near  the  end  of  the  opened  part  of  the  tunnel, 
which  is  815  feet  long,  the  cross-section  is  in  horizontally 
bedded  sandstone,  with  narrow  seams  of  black  clay  and  quartz, 
which  underlies  the  black  gouge.  On  the  hillside  above  this 
tunnel  are  prominent  croppings  of  the  breccia. 

The  ore  bodies  in  these  works  have  never  been  connected 

with  those  in  the  underground 
works  in  the  main  tunnel,  and 
appear  to  be  a  separate  deposit. 
From  the  fact  that  in  the  sand- 
stone tunnel  cinnabar  is  found 
in  the  sandstone,  it  must  be 
concluded  that  the  ore  deposi- 
tion took  place  through  water 

Fig.  46.     Elevation  open  cut  (  ^ ),  Cerro  i  i  .,•  .■,  ■%      .i   • 

Bonito  Mine.  chanuds  cutting  through  this 

sandstone;  but  the  occurrence 
of  the  recemented  breccia  so  extensively  overhing  unaltered 
and  undisturbed  sandstone  is  as  yet  unexplained.  The  large 
bodies  of  black  gouge  (attrition  products),  showing  very  impor- 
tant movements  in  the  strata  resting  upon  these  same  sand- 
stone beds,  render  the  explanation  all  the  more  difficult.  It  is 
hardly  conceivable  that  all  this  metamorphic  material  has  been 
moved  into  its  present  position  by  dynamic  action  finding  its 
center  in  Cerro  Bonito  Hill.  The  surface  workings  show  a 
stratum  of  serpentine,  or  may  be  serpentinized  material,  under- 
Ij'ing  the  breccia  forming  the  croppings  and  lying  unconforma- 
bly  on  the  sandstones  and  shales.  [See  Fig.  46.]  The  croppings 
southwest  of  the  discovery  point,  wherein  a  short  tunnel  and 
a  shallow  shaft  are  located,  are  much  more  serpentinized  and 


SAN    BENITO    COUNTY.  137 

show  some  cinnabar  all  through  in  a  softer,  more  weathered 
material  than  in  the  other  croppings. 

The  cinnabar  forms  generally  in  the  hard,  siliceous  brecciated 
material,  which  may  be  considered  the  gangue  rock.  It  is 
claimed  that  verj^  rich  ore  was  found  in  the  surface  openings, 
though  none  is  at  present  visible;  it  was  probably  in  the  softer 
and  more  open  parts  of  the  rock. 

The  vicinity  of  this  mine  is  supplied  with  timber  for  both 
mining  and  fuel  purposes.  The  mine  is  3  miles  from  Llanada, 
a  stage  station  31  miles  from  Tres  Pinos. 

Clear  Creek  Mine  and  adjacent  Boston  Mine,  also  called  the 
Monterey  Mine.  New  Idria  District.  In  Sees.  2,  11,  and  12, 
T.  18  S.,  R.  II  E.  Thomas  Flint,  of  Hollister.  owner.  These 
mines  lie  on  a  line  of  croppings  which  run  from  the  northern 
end  of  the  Clear  Creek  mine  in  a  direction  about  S.  30°  E.  to 
the  Los  Picachos  mine,  in  Sees.  19  and  20,  T.  18  S.,  R.  12  E.; 
passing  through  the  Andy  Johnson  mine.  They  are  not  con- 
tinuous, but  show  suflSciently  to  trace  their  line.  These  crop- 
pings are  of  a  light  yellow  ochery  material,  traversed  by  a 
network  of  quartz  veins  and  some  serpentine  seams.  In  places 
the  rock  contains  a  great  amount  of  iron  oxide,  becoming 
brownish-red  in  color.  The  cinnabar  appears  to  be  scattered 
all  through  the  rock  in  those  places  where  it  is  mineralized. 

The  upper  croppings  of  the  Clear  Creek  mine,  590  feet  above 
the  level  of  the  creek,  have  been  extensively  worked  and  a 
road  has  been  built  from  there  to  the  furnace  in  the  creek. 
The  lower  croppings,  305  feet  above  the  same  level,  also  show 
extensive  operations,  and  some  good  ore  can  yet  be  found  on 
the  dump.  The  cinnabar  is  scattered  through  the  rock  in 
crystalline  aggregates  and  along  the  fracture  seams.  While  no 
pyritic  ore  is  found  on  the  dump,  it  is  more  than  probable  that 
it  will  prove  to  be  the  same  mass  of  silica,  highly  permeated 
with  iron  sulphide,  found  in  the  Los  Picachos  mine.  Between 
the  croppings  and  the  creek  level  some  remnants  of  an  almost 
entirely  covered-up  tunnel  can  be  seen,  and  a  long  tunnel  has 
been  run  on  the  line  of  the  croppings  about  N.  30*^  \V.  at  the 
level  of  the  creek,  but  is  at  present  inaccessible.  About  one 
mile  below  this  mine  is  a  dismantled  furnace. 

Don  Juan  and  Don  Miguel  Mines. — This  group,  also  called  the 
San  Benito,  and  sometimes  the  Cody  mine.  New  Idria  District, 


138  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

is  in  Sec.  36,  T.  18  S.,  R.  11  E.,  and  Sec.  31,  T.  iS  S.,  R.  12  E. 
Estate  of  E.  J.  Breen,  San  Francisco,  owner.  The  works  are 
inaccessible,  but  judging  from  the  dumps  the  ore  forms  in  a 
shale  interstratified  with  thin  layers  of  sandstone,  which  in  the 
rock  exposed  to  the  air  is  colored  brown  by  oxide  of  iron.  The 
cinnabar  forms  in  the  cross  joints  of  the  undisturbed  rocks,  and 
in  crushed  pieces  along  the  fracture  planes.  The  main  tunnel 
is  45  feet  above  the  level  of  the  creek.  The  ore  was  followed 
down  with  a  shaft  until  the  water  came  in  too  freely  to  be 
handled.  The  strike  of  the  croppings  is  northwesterly.  To 
the  southeast  they  abut  against  a  body  of  sandstone,  which 
can  be  seen,  in  the  canon  running  into  the  San  Benito  above  the 
mine,  to  be  overh'ing  the  metamorphic  shales.  The  latter  have 
an  east  and  west  strike,  dipping  southerlj'  70°. 

Fourth  of  July  Mine,— New  Idria  District.  In  Sec.  18,  T.  18  S., 
R.  12  E.  Thomas  Flint,  of  Hollister,  owner.  This  property 
is  located  on  a  line  of  croppings  running  about  parallel  to  the 
northeast  and  lower  down  the  ridge  than  those  of  the  Andy 
Johnson.     None  of  the  old  workings  are  accessible. 

Mariposa  Mine. — Stayton  District.      [See  Santa  Cruz  Mine.] 

New  Idria  Mine. — This  property  is  situated  in  Sees.  29  and  32, 
and  parts  of  28,  33,  34,  and  35,  T.  17  S.,  R.  12  E.,  and  Sees. 
3  and  4,  T.  18  S.,  R.  12  E.  The  New  Idria  Quicksilver  Mining 
Companj-,  owner;  B.  M.  Newcomb,  general  superintendent.  Oat- 
hill,  Napa  County;  J.  G.  Finch,  superintendent.  New  Idria,  San 
Benito  County.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  291 ;  Report 
State  Mining  Bureau  of  Cal.,  VIII,  page  483;  XI,  page  373; 
XIII,  page  599.] 

Several  mines  are  embraced  under  this  heading:  as  the 
Washington,  New  Idria,  Sulphur  Spring,  Molina,  and  San 
Carlos  mines.  The  mines  were  discovered  and  located  in  1853, 
and  several  of  them  have  been  operated  to  a  greater  or  less 
extent  since  that  time  almost  continuously.  The  company 
operating  the  property  at  present  acquired  it  by  purchase  in 
1895,  and  has  since  made  manj-  and  extensive  changes  in  the 
earlier  mining  and  reduction  methods,  so  that  the  works  of 
to-day  present  a  different  aspect  from  those  described  b}-  Dr. 
Becker. 

The  New  Idria  mine  is  the  principal  and  the  largest  profit- 
producer   of  all    the    mines    of  the    group.     Several    miles    of 


140 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


underground  work  have  been  developed  in  this  mine,  of  which 
over  two  miles  are  at  present  open. 

The  Xew  Hope  vein  has  not  been  w^orked  for  years,  and 
what  Dr.  Becker  called  the  stockwercks  forms  at  present  the 


N 


X\:s  'Sha/es     one/ 


Co 


•some 


sondsfone 


New    Id 


ria 


Shale 


>■ 


L. 


'Ivan  6frea/f/n  /he  A/e^  /dna  /^/ne 


StbLEl/ri 


Fig    47.    Xew  Idria  Mine. 


main  worked  ore  deposit,  called  the  Xew  Idria.  [See  Figs.  47 
and  48.]  This  deposit  has  been  followed  downward  to  the 
700-foot  level.  Its  hanging  w^all  is  the  cla}-  wall  of  Dr.  Becker; 
the  foot  wall  is  a  shale.     The  Elvan  vein  has  been  extensivelv 


SAN    BENITO    COUNTY. 


141 


worked,  and  is  at  present  worked  between  the  500  and  700-foot 
levels.     The  Bell  tunnel  is  at  present  inaccessible. 

The  accompanying  sketch  [Fig.  48]  shows  that  the  deposit 
has  a  southerly  dip.  The  stratification  of  the  rock  in  the  ore 
bod}'  is,  however,  to  the  north. 


/^  -longing  tTa// 
^  -foor  Wa// 


Fig    48. 

The  ore  makes  as  a  rule  in  a  more  or  less  metamorphic 
sandstone,  but  occasionally  in  metamorphic  shale.  This  deposit 
is  strongly  marked  at  the  surface  by  a  line  of  very  bold  crop- 
pings,  in  places  standing  out  over  100  feet  above  the  hillside. 
The  general  course  of  these  croppings  is  about  S.  80°  W. 
The  material  of  these  croppings  is  a  highly  metamorphosed 
sandstone,   wherein    some    less   altered    sandstone  occurs  and 


142  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

mixed  with  some  indurated  shale,  in  places  containing  a 
great  amount  of  pj^rites  and  their  oxidation  products.  The 
rock,  especially  the  softer  parts,  is  impregnated  with  cinnabar, 
and  small  aggregates  of  cinnabar  crystals  are  found  dissemi- 
nated through  very  hard  rock.  The  fissures  and  cracks  are 
often  found  filled  with  cinnabar,  accompanied  with  calcite  and 
some  quartz.  The  ledge  matter  contains  sensible  amounts  of 
sulphur. 

Near  the  western  edge  of  the  croppings  a  very  good  expo- 
sure of  the  formation  is  found,  showing  the  clay  wall  about 
ID  feet  thick,  course  N.  50°  E.,  dipping  S.W.  65°,  overlaid  by 
shales,  and  in  its  turn  overlying  sandstone. 

The  serpentine  is  a  few  hundred  feet  from  the  New  Idria 
vein  at  the  surface,  but  does  not  form  either  wall  permanently 

as  far  as  at  present  developed.  In 
the  500-foot  level  it  occurs  at  the 
western  end  overlying  the  clay  wall. 
[See  Fig.  49.]  In  the  700-foot  level 
a  gouge  seam  containing  serpentine 
is  found  in  the  ore  body,  which 
would  lead  one  to  expect  that  at 
greater  depth  the  serpentine  may  be- 
come the  hanging  wall. 
'5  Referring  to  Figure  47,  it  can  be 

Fig  49.   Section  west  end  fifth     sccu  that  the  orc  body  lies  on  an  arc 

level.  New  Idria  Mine.  ^f     ^    Circlc,     the    Walls    ClOsing    iu    at 

both  ends.  The  Elvan  vein  is  closely  connected  with  the  New 
Idria  ore  body,  but  the  New  Hope  seems  to  be  independent 
and,  as  Dr.  Becker  obsen-ed,  does  not  appear  to  pass  the  clay 
wall  to  the  northwest. 

The  New  Idria  vein  is  very  persistent  in  depth;  in  fact,  shows 
on  the  lowest  level  as  good,  if  not  better  ore  than  in  the  upper 
part  of  the  mine.  The  width  of  the  workable  ore  bodies  is 
very  irregular.  In  places  they  are  100  feet  wide;  in  other 
parts  of  the  mine  the  entire  body  between  walls  is  either 
barren  or  so  low  grade  as  to  be  unworkable.  The  average  dip 
may  be  placed  at  50^-55°.  The  cinnabar  content  of  the  differ- 
ent portions  of  the  mine  depends  partly  on  the  physical  char- 
acter of  the  rock.  Where  the  latter  is  strongly  crushed  it 
contains  more  cinnabar,  yet  in  places  very  hard  rock  is  so 
thoroughl}'  impregnated  with  cinnabar  that  it  becomes  good 


SAN    BENITO    COUNTY.  143 

workable  ore.  The  presence  of  the  cinnabar  in  this  hard  rock 
can  only  be  explained  by  deposition  from  solutions  by  circulat- 
ing in  sub-capillar>'  channels,  hence  in  the  deep  zone  of  rock 
fiowage. 

The  ore  is  accompanied  by  sensible  amounts  of  gypsum,  due 
probabh'  to  the  great  amount  of  sulphur  already  mentioned. 
The  clay  wall  is  probably  a  gouge  resulting  from  a  movement 
lietween  the  strata,  which  faulted  the  formation,  and  at  the 
place  of  faulting  crushed  the  rock,  thereby  causing  a  zone  emi- 
nently predisposed  for  ore  deposition.  The  clay  wall  has  as 
yet  not  been  prospected  any  distance  on  either  side  of  the  Xew 
Idria  ore  body.  It  is  probable  that  other  ore  bodies  will  be 
found  on  this  line  of  fracturing.  The  ground  in  the  mine  is 
rather  heavy,  requiring  square-set  timbering  and  filling  in  the 
stopes. 

Through  a  very  well-conceived  plan  of  chutes  throughout  the 
mine  and  b)'  the  use  of  an  old  incline  shaft  connecting  the  500 
and  the  700-foot  levels,  all  ore  broken  in  the  mine  can  be  sent 
down  to  the  latter  level,  from  which  point  it  is  carried  by 
tramway  to  ore  bins  located  on  the  hillside  above  the  reduction 
works,  where,  after  passing  over  grizzlies,  it  is  distributed  by  two 
gravity  tramways  to  the  fine  and  coarse  ore  furnaces  respec- 
tively. A  considerable  portion  of  the  ore  treated  is  obtained 
from  the  surface,  part  of  it  being  from  the  croppings  before 
described,  and  part  from  the  old  dumps,  the  resultants  of  earl 5' 
years'  working.  Much  of  this  material  finds  its  way  to  the 
reduction  works  through  the  same  channel  as  above  described. 
[See  Fig.  47.]  Thus  the  cost  of  its  transportation  from  the 
mine  to  the  reduction  works  is  minimized. 

The  timbers  in  the  700-foot  level  are  coated  with  whitewash. 
By  this  very  simple  method  these  mining  timbers,  which  were 
formerly  covered  by  fungi  and  destroyed  by  the  acids  in  the  mine 
water  within  a  few  months,  now  remain  entirely  sound  after 
having  been  in  the  mine  over  eighteen  months. 

The  mine  is  equipped  with  a  Scott  fine-ore  furnace  handling 
60  tons  per  twenty-four  hours,  and  a  coarse-ore  furnace  han- 
dling nearly  100  tons  per  twenty-four  hours.  [See  chapter  on 
Aretallurgy.  page  197.] 

San  Carlos  Mine. — Xew  Idria  District.  This  is  in  Sec.  4, 
T.  18  S.,  R.  12  E.,  and  forms  one  of  the  group  of  mines  of  the 


144  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

New  Idria  Company.  This  mine  was  discovered  in  1858  and 
was  worked  to  a  very  limited  extent — more  in  the  nature  of 
surface  prospecting  than  as  legitimate  mining  work;  but  in 
later  years  discoveries  of  ver^-  rich  superficial  ore  bodies  were 
made,  and  were  worked  over  quite  an  extent  of  surface,  with 
great  profit  to  the  owners.  Late  workings  have  so  far  failed 
to  discover  any  deep  deposits  of  value.  As  will  be  seen  from 
the  map  of  the  district  no  serpentine  appears  at  the  surface  in 
the  ground  covered  b}'  this  mine.  The  country  rock  is  princi- 
pally metamorphic  shales  and  sandstone.  Some  of  the  rock 
has  the  appearance  of  a  probable  igneous  origin. 

Plan 

^ N70'L-I50 

%  oandsrone 

%  °  /  i  I 

"S/ia/es   I   1 


Shty/e  &^y^^^^^^^=::r-~~....^       front    Elevaf/on 
Serpent^ 


Fig.  50.     Open  cut,  San  Carlos  Mine. 

{a)  Drift  in  altered  shale. 

(b)  Sandstone  carrj-ing  some  cinnabar. 

( (/)  Decomposed  serpentine  dipping  a  little  north  of  east. 

{/)  Very  hard  silicified  serpentine  carrying  cinnabar. 

In  the  face  of  one  of  the  open  cuts  [see  Fig.  50]  serpentine 
is  found  containing  sensible  amounts  of  cinnabar.  This  ser- 
pentine overlies  the  shales,  and  from  the  appearance  of  the  cuts 
both  the  shales  and  the  sandstone  carried  cinnabar;  but  this 
ore  did  not  persist  to  any  considerable  depth.  The  ore  formed 
in  all  formations,  but  the  channels  through  which  it  reached 
the  surface  are  as  3'et  unproven. 

Two  tunnels  have  been  run  in  a  northeasterh-  direction  from 
the  northwest  side  of  the  peak  under  the  open  cuts,  about  100 
feet  below  their  bottom.     These  tunnels  run  principalh-  through 


SAN    BENITO    COUNTY.  145 

metamorphic  shale.  Some  ore  was  found  in  them,  but  not  in 
such  quantity  or  position  as  to  justify  the  assumption  that  the 
channel  through  which  these  extensive  deposits  at  the  surface 
were  fed  has  been  intersected. 

A  crosscut  tunnel,  260  feet  below  the  latter  tunnels  and 
started  from  the  south  side  of  the  peak,  is  now  iioo  feet  in, 
running  on  a  course  nearly  X.  60°  W.,  but  has  not  reached  the 
territory  under  the  open  cuts.  This  tunnel  runs  through  meta- 
morphic shales  and  sandstones.  For  the  first  500  feet  the  strata 
are  much  distorted  and  crushed,  but  after  passing  through 
about  50  feet  of  indurated  black  cla^^  stratified  in  nearly  verti- 
cal beds  and  having  a  strike  of  about  X.  70°  W.,  the  formation 
becomes  more  regular,  both  the  shales  and  sandstones  having 
conformable  strata.  Xearer  the  breast  sandstones  prevail, 
while  in  the  first  part  of  the  tunnel  shales  are  the  prevailing 
material.  In  a  gouge  seam,  standing  nearly  vertical  and  cut- 
ting through  sandstone,  are  found  several  quartz  seams,  some 
having  large  quartz  crystals.  Gypsum  and  calcite  are  found 
in  the  seams  of  the  shales.  Xear  the  breast  the  sandstone  has 
inclusions  of  fine-textured  rock,  and  in  some  of  the  seams 
carries  chalcopyrite. 

Philadelphia  and  New  York  Mines, — Xew  Idria  District.  In 
Sees.  23,  25,  and  26,  T.  iS  S.,  R.  11  E.  Estate  of  E.  J.  Breen, 
San  Francisco,  owner.  They  are  located  on  a  stratified  shale, 
colored  deeply  red  with  oxide  of  iron.  These  shales  have  a 
strike  about  southeast,  dip  southwesterly,  which  strike  brings 
them  about  in  the  direction  of  the  Don  Juan  mine,  higher  up 
San  Benito  Creek.  In  the  northwestern  part  of  the  property, 
in  the  Philadelphia  claim,  considerable  work  has  been  done, 
consisting  of  a  tunnel  100  feet  long,  course  northeast,  a  large 
open  cut  in  the  steep  hillside,  and  a  smaller  cut  with  a  short 
tunnel,  125  feet  above  the  tunnel.  There  are  no  signs  of  cin- 
nabar ore  in  the  works  or  on  the  dump.  In  the  New  York 
mine  little  or  no  work  has  been  done. 

Ramirez  Consolidated  Mine  (formerly  Los  Picachos  Mine).— 
New  Idria  District.  In  Sees.  19  and  20,  T.  18  S.,  R.  12  E. 
\V.  A.  Stuart,  and  others,  owners,  Xo.  606  Montgomery  street, 
San  Francisco.  This  mine  derived  its  name  of  Los  Picachos 
from  a  series  of  bluffs  cropping  boldly  above  the  hillside  to  au 


146 


QUICKSILVER    RESOURCES   OF    CALIFORNIA. 


elevation  of  from  loo  to  250  feet.  These  bluflEs  belong  to  the  sys- 
tem of  croppings  showing  at  the  surface  in  a  line,  having  a 
course  X.  30^  W.,  from  this  mine  across  the  Andy  Johnson  to  the 
north  end  of  the  Clear  Creek  mine,  a  distance  of  over  four 
miles.  The  croppings  on  this  mine  are  not  onh-  bolder,  but 
also  delineate  both  sides  of  a  bod}-  of  siliceous  rock  cutting 
through  the  serpentine  countn,',  having  a  width  of  from  300 
to  600  feet.     To  the  southeast  thev  can  not  be  found  further 


PHOTO  No.  13.     LOS  PICACHOS  MINE  (RAMIREZ  CONSOLIDATED) 

than  the  southeastern  Picachos  Peak.  Beyond  the  creek  cours- 
ing around  that  knoll  is  only  the  barren  serpentine,  without 
any  trace  of  mineralization.  At  the  surface  the  croppings  are 
highly  colored  by  the  oxidation  of  the  iron  pyrites,  in  places 
mixed  with  chalcopj'rite.  which  is  found  in  great  amount  in 
the  unaltered  rock.  In  the  weathered  rock  cinnabar  is  found 
in  the  fracture  planes  in  seams  of  more  or  less  thickness;  also 
in  bedding  planes  and  in  places  in  crushed  zones  of  the  rock. 
In  the  unaltered  rock,  cinnabar  occurs  mainly  as  a  coating  of 
vugs.     After  this  cinnabar  was  deposited  a  posterior  deposition 


SAN    BENITO    COUNTY.  147 

of  silica  took  place,  covering  the  cinnabar.  The  rock  itself  is 
not  impregnated  with  cinnabar,  probably  due  to  its  compact- 
ness. The  face  of  the  bluffs  shows  a  stratification  in  the  rock 
forming  the  croppings;  in  the  southeastern  part  of  the  property 
the  strata  have  a  strike  S.  40°  E.,  dipping  N.E.  60*^.  The  cin- 
nabar is  found  in  the  bedding  planes;  in  other  places  cinnabar 
is  found  in  the  joint  planes.  In  the  northwestern  part  of  the 
mine  these  strata  have  a  strike  N.  30°  E.,  and  dip  southeast. 
The  line  of  the  croppings  is  not  quite  straight,  while  in  the 
southeast  portion  the  strike  is  parallel  with  that  of  the  crop- 
pings; it  is  across  that  of  the  croppings  in  the  northwestern 
portion. 

There  are  a  great  number  of  old  workings,  which  at  present 
are  inaccessible,  and  the  remnants  of  an  old  furnace.  The 
present  owners  are  doing  some  surface  development,  having 
some  good  ore  at  the  surface.  The  mine  is  equipped  with  a 
i2-pipe  retort  furnace. 

Santa  Cruz  and  Mariposa  Mines. — Stayton  Mining  District.  In 
Sees.  20,  21,  28,  and  29,  T.  11  S.,  R.  7  E..  at  the  western  foot 
of  Mariposa  Peak.  H.  French,  of  Lone  Tree,  San  Benito 
County,  owner.  [See  Report  State  Mining  Bureau  of  Cal.,  XII, 
pages  365  and  366.]  These  mines  are  in  a  verj'  thoroughly 
decomposed  igneous  rock.  The  old  works  give  out  verj-  strong 
sulphur  emanations.  In  former  years  they  yielded  some  quick- 
silver by  retorting,  but  are  at  present  virtually  abandoned. 

Stayton  Mines,  including  the  Gypsy,  are  located  in  Sees.  5  and 
8,  T.  12  S.,  R.  7  E.,  partly  in  San  Benito  and  partly  in  Merced 
counties.  The  Staj'ton  Mining  Company,  owner;  S.  H.  Smith, 
secretary  and  general  manager,  Gilroy,  Santa  Clara  County. 
[See  Report  State  Mining  Bureau  of  Cal.,  VIII,  page  350;  X, 
page  515;  XI.  page  371;  XII,  page  365;  XIII,  page  599.] 
These  mines  were  discovered  early  in  the  70's  and  worked  for 
some  years  up  to  1877.  Considerable  ore  was  taken  out  and 
worked  in  one  Q  retort.  The  Gypsy  mine,  which  now  forms 
part  of  this  property,  was  worked  in  former  years  by  several 
parties.  The  last  separate  owner,  the  San  Benito  Mining 
Company,  erected  a  lo-ton  fine-ore  Scott  furnace,  which,  how- 
ever, was  never  put  in  practical  operation.  It  is  stated  that 
this  property  has  produced  between  800  and  1000  flasks  by  the 
retorting  process. 

10 — QR 


148 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


The  mines  are  located  on  both  slopes  of  the  main  ridge  of 
the  Mount  Diablo  range.  The  principal  cinnabar  deposits  are 
to  the  east  of  the  range,  mostly  accompanied  by  some  stibnite; 
but  some  cinnabar-carr\-ing  veins  are  found  west  thereof,  in 
which  territory,  however,  the  principal  ore  deposits  are  exclu- 
sively stibnite. 

The  workings  on  the  cinnabar  deposits  are  very  shallow; 
the  deepest  workings  in  the  Excelsior  mine  are  not  over  140 
feet  on  the  dip  of  the  vein.  [See  g,  map  of  Stayton  Mining 
District.]  A  tunnel  (/)  over  1200  feet  long,  in  a  direction 
nearlj'  perpendicular  to  the  general  strike  of  the  mineralized 
zone,  cuts  the  formation  at  the  deepest  point  at  a  vertical 
depth  of  about  300  feet.     It  is  inaccessible,  but  judging  from 

the  dump  the  material  is  princi- 
palh*,  if  not  exclusively,  igne- 
ous. The  strike  of  the  mineral- 
ized zones  east  of  the  main 
ridge  is  nearly  north  and  south, 
and  from  south  of  the  cabin  to 
g,  a  distance  of  over  three 
fourths  of  a  mile,  the  cinnabar- 
canying  ledge  matter  is  exposed 
in  several  places,  dipping  west 
at  an  angle  of  about  45*^.  To 
the  east  of  this  zone  lies  in  its 
southern  part  a  belt  of  basalt.  The  ledge  matter  is  an  altered 
rhyolite,  containing  besides  cinnabar,  iron  sulphides,  gypsum, 
and  occasionally  some  stibnite.  In  the  southern  part,  North 
Star  {b)  and  Graybuck  {a)  workings  [see  Fig.  51],  this  ledge 
matter  is  associated  with  a  belt  of  chalcedonic  quartz,  and  in 
places  the  cinnabar  has  formed  as  cavit}-  filling  associated  with 
quartz  cr^'stallization.  This  ledge  matter  contains  bunches  of 
iron  pyrites,  in  places  rich  in  copper.  In  the  northern  part  at 
g  the  cinnabar  forms  in  a  material  which  to  the  naked  eye  has 
the  appearance  of  a  breccia,  but  under  the  glass  is  shown  to 
consist  of  a  dark-colored,  close-grained  quartz,  the  darker 
coloring  being  due  to  iron  and  antimony  minerals,  with  inclu- 
sions of  much  lighter-colored  quartz.  The  ledge  filling  then 
shows  strong  sulphurization  and  silicification  actions,  both 
contemporaneous  with  the  ore  deposition.  The  main  ledge  is 
accompanied  by  a  number  of   small  fissures  striking  a  little 


Fig.  51. 


Section  at  Graybuck  shaft, 
Stavton  Mine. 


SAN    LUIS    OBISPO    COUNTY. 


149 


■  1  /,i 


//        ^ 


QVi 


Drawr 


\ 


^ 


>.rthyoi\y 


i^  A-^^ 


SAN    LUIS    OBISPO    COUNTY,  149 

east  of  south  and  dipping  nearly  vertical,  running  from  the 
west  to  the  main  ledge  both  in  strike  and  dip,  a  number  of 
which  contained  some  very  rich  ore,  especially  near  the  sur- 
face, but  none  has  as  yet  been  followed  to  its  contact  with  the 
main  ledge;  hence  the  question  whether  or  not  they  belong  to 
the  same  fracture  system  is  as  yet  unanswered. 

As  above  stated,  antimony  forms  the  principal  metallic  ore 
west  of  the  ridge,  yet  two  cinnabar  deposits  are  found  there, 
close  to  the  top  of  the  main  ridge.  One,  the  Pacific  (//),  is 
situated  on  a  belt  of  sandstone  running  north  and  south,  dip- 
ping east  75°,  having  a  seam  of  cinnabar  ore  i8  inches  wide. 
In  close  vicinity  are  found  stibnite  croppings,  striking  north- 
west and  dipping  northeast.  The  other  cinnabar  deposit  (/), 
near  the  road  on  the  divide,  is  associated  with  a  prominent  belt 
of  leached  siliceous  rocks,  showing  very  peculiar  cavities. 

SAN  LUIS  OBISPO  COUNTY. 

General  Geology. — The  Santa  Lucia  range  and  its  spurs  cover 
the  northwestern  part  of  San  Luis  Obispo  County,  in  which 
section  are  located  nearly  all  the  quicksilver  deposits  of  the 
county.  They  are  located  in  zones  separated  by  large  sections 
of  country,  which  sections,  as  far  as  yet  ascertained,  are  barren. 
In  the  northwestern  part  of  this  territory  near  Pine  Mountain 
there  is  a  line  of  cones  formed  of  rhyolite,  having  a  general 
northwestern  direction.  The  cones,  while  close  together,  are 
not  connected  at  the  surface.  Near  Pine  Mountain,  among  the 
debris  of  the  rhyolite  covering  the  slopes  of  the  cones,  are 
found  bowlders  of  diorite,  indicating  prior  igneous  eruptions. 

In  the  Adelaide  and  Oceanic  districts  some  scattered 
exposures  of  rhyolite  are  found,  which  have  no  apparent  rela- 
tion to  each  other;  hence  nothing  can  be  inferred  relative  to 
the  dislocations  which  caused  these  eruptions.  The  serpen- 
tine lies  principally  on  the  west  slope  of  the  main  ridge,  where 
it  has  caused  enormous  slides,  due  to  its  deterioration  by 
atmospheric  influences.  Its  principal  exposure  is  at  Cypress 
Mountain,  where,  at  several  places,  its  contact  can  be  seen 
with  the  underlying  partly  altered  sandstones.  The  entire 
appearance  of  the  serpentine  mass  tends  to  the  supposition 
that  it  is  an  altered  peridotite.  In  one  place  on  the  northwest 
slope  of  the  mountain  some  signs  of  induration  by  contact  met- 


148  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


—•J —   „f 


-  ri 


A 


Y8    030621 

UAjf^Oa  OMIHIM   3TATe^ 

YflUSUA.a  3IW3J  j 

-  !>ff)0JAR3V«»«  3TAtT3  / 

eoet 


jiMi  ^-iDnir 


I    /lAr 


^.^v■o.^"t\•^? 


\\',A<'<C,0\A>."\    .V 


•■'•.  d > o\  .rr<NN  -^^^    -^j^  ^\ t^^*^ 


•  lOrrfiifiH.O   \A  n-Hi 


SAN    LUIS    OBISPO    COUNTY.  149 

east  of  south  and  dipping  nearly  vertical,  running  from  the 
west  to  the  main  ledge  both  in  strike  and  dip,  a  number  of 
which  contained  some  very  rich  ore,  especially  near  the  sur- 
face, but  none  has  as  yet  been  followed  to  its  contact  with  the 
main  ledge;  hence  the  question  whether  or  not  they  belong  to 
the  same  fracture  system  is  as  yet  unanswered. 

As  above  stated,  antimony  forms  the  principal  metallic  ore 
west  of  the  ridge,  yet  two  cinnabar  deposits  are  found  there, 
close  to  the  top  of  the  main  ridge.  One,  the  Pacific  (//),  is 
situated  on  a  belt  of  sandstone  running  north  and  south,  dip- 
ping east  75°,  having  a  seam  of  cinnabar  ore  i8  inches  wide. 
In  close  vicinity  are  found  stibnite  croppings,  striking  north- 
west and  dipping  northeast.  The  other  cinnabar  deposit  (/), 
near  the  road  on  the  divide,  is  associated  with  a  prominent  belt 
of  leached  siliceous  rocks,  showing  verj'  peculiar  cavities. 

SAN  LUIS  OBISPO  COUNTY. 

General  Geology. — The  Santa  Ivucia  range  and  its  spurs  cover 
the  northwestern  part  of  San  Luis  Obispo  County,  in  which 
section  are  located  nearly  all  the  quicksilver  deposits  of  the 
county.  They  are  located  in  zones  separated  by  large  sections 
of  countr}-,  which  sections,  as  far  as  j-et  ascertained,  are  barren. 
In  the  northwestern  part  of  this  territory  near  Pine  Mountain 
there  is  a  line  of  cones  formed  of  rhj'olite,  having  a  general 
northwestern  direction.  The  cones,  while  close  together,  are 
not  connected  at  the  surface.  Near  Pine  Mountain,  among  the 
debris  of  the  rhyolite  covering  the  slopes  of  the  cones,  are 
found  bowlders  of  diorite,  indicating  prior  igneous  eruptions. 

In  the  Adelaide  and  Oceanic  districts  some  scattered 
exposures  of  rhyolite  are  found,  which  have  no  apparent  rela- 
tion to  each  other;  hence  nothing  can  be  inferred  relative  to 
the  dislocations  which  caused  these  eruptions.  The  serpen- 
tine lies  principally  on  the  west  slope  of  the  main  ridge,  where 
it  has  caused  enormous  slides,  due  to  its  deterioration  by 
atmospheric  influences.  Its  principal  exposure  is  at  Cypress 
Mountain,  where,  at  several  places,  its  contact  can  be  seen 
with  the  underlying  partly  altered  sandstones.  The  entire 
appearance  of  the  serpentine  mass  tends  to  the  supposition 
that  it  is  an  altered  peridotite.  In  one  place  on  the  northwest 
slope  of  the  mountain  some  signs  of  induration  by  contact  met- 


150  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

amorphism  of  the  adjoining  sandstone  can  be  found.  The  Fran- 
ciscan series  are  prominently  represented  b\-  sandstones,  which 
are  ^"ery  irregular  in  texture,  grading  from  entirelj^  unaltered 
arkose  sandstones  into  completely'  metamorphosed  sandstones, 
nearly,  if  not  entirelj-  quartzite.  and  these  various  phases  are 
intimately  mixed,  without  any  traceable  S3-stem  of  gradation. 

Adelaide  District. — This  district  comprises  the  main  range  from 
Cypress  Mountain,  in  Sec.  i,  T.  27  S..  R.  9  E.,  to  the  Madrone, 
in  Sec.  22,  T.  27  S.,  R.  10  E.,  with  the  territory  on  the  north- 
east slope,  covering  the  headwaters  of  Las  Tablas  and  El  Paso 
Robles  creeks.  The  rocks  of  this  district  belong  prominently 
to  the  Franciscan  or  metamorphic  series,  principally  sandstones, 
with  occasionally  some  shales,  and  in  a  few  places  exposures  of 
chert  beds.  One  wide  body  of  serpentine  is  found  at  Cypress 
Mountain,  extending  southward  past  the  headwaters  of  Santa 
Rosa  Creek.  The  whole  belt  has  a  northwest  trend,  and  a  nar- 
rower and  shorter  belt  of  serpentine  lies  west  thereof.  In  the 
northern  part  of  the  district,  on  the  main  ridge,  north  of 
Cypress  Mountain,  is  an  exposure  of  rhyolite,  belonging  to  the 
scattered  exposures  above  mentioned;  it  has  a  northern  trend, 
but  is  of  relatively  small  dimensions. 

The  territory  comprising  this  district  must  at  one  time  have 
been  covered  by  the  Chico  series.  It  is  bounded  on  the  east 
and  northeast  by  the  Chico  sandstone,  and  in  places  larger  and 
smaller  patches  of  the  same  are  found  on  the  top  of  the  ridges, 
the  Franciscan  rocks  being  exposed  lower  down  the  hillside  or 
in  the  canons.  At  the  contact,  the  Chico  sandstones  are  so 
much  broken  up  and  contorted  that  it  is  impossible  to  give  any 
data  as  to  the  strike  and  dip  of  the  beds. 

A  line  of  croppings  which  can  readily  be  followed  runs  in 
a  northwesterly  direction  through  this  district;  though  more 
or  less  parallel  to  the  direction  of  the  main  ridge  of  the  Santa 
Lucia  range,  this  line  is  clearly  independent  thereof.  These 
croppings,  starting  from  the  southern  part  of  the  district  in  the 
Madrone  property,  run  continuously  through  the  La  Libertad, 
Josephine,  Alice,  Modoc,  and  Elizabeth  mines.  Then  the^' 
become  much  less  prominent  and  only  show  occasionally  in 
the  ridge  between  Johnson  and  Carmine  creeks  and  farther 
north  toward  the  Cypress  Mountain  group.  The  Karl  and 
Mahoney  mines  are  situated  on  a  belt  entirely  disconnected 
from  these  croppings. 


SAN   LUIS   OBISPO   COUNTY.  151 

The  ore  in  this  district  is  generally  a  whitish  quartzose 
material,  containing  small  inclusions  of  serpentine,  the  cinnabar 
forming  principally  in  the  seams,  which  show  signs  of  later 
silicification.  The  cinnabar  is  often  accompanied  by  sensible 
amounts  of  iron  sulphides,  which  by  their  oxidation  near  the 
surface  give  an  ochery  yellow  color  to  the  ore.  As  a  rule,  the 
ore  carries  more  iron  sulphides  as  the  cinnabar  contents 
increase.  The  ore  bodies  are  contiguous  to  more  or  less  exten- 
sive strata  of  dark-gray  to  black-colored  clays,  mixed  with 
bowlders  of  lighter  gray-colored  sandstones.  They  are  of  the 
same  nature  as  that  of  the  black  clays,  generalh^  associated 
with  quicksilver  deposits — "alta,"  only  here  they  are  almost 
invariably  indurated.  Their  outcrops  frequently  accompany 
those  of  the  ore  bodies;  the}-  are  of  a  light  gray  color,  having 
the  appearance  of  a  disintegrated  sandstone,  traversed  by  a 
network  of  narrow  seams  of  an  ochreous  yellow  color;  in  places 
small  inclusions  of  serpentine  are  found.  This  material,  while 
contiguous  to  the  ore  deposits,  is  always  barren  of  cinnabar. 

A  great  amount  of  work  has  been  done  in  this  district,  espe- 
cially between  1S67  and  1872;  but  in  no  mine,  except  the  Karl, 
has  sufficient  development  work  been  done  to  enable  one  to 
judge  as  to  the  behavior  of  the  ore  bodies  in  depth.  In  several 
properties  the  surface  disclosures  would  fully  justify  systematic 
development  work.  The  policy,  however,  seems  generally'  to 
be  to  hunt  for  pockets  of  rich  ore,  which  is  treated  in  retort 
furnaces,  instead  of  opening  large  bodies  of  furnace  material. 

Oceanic  District* — This  district  is  situated  on  the  west  slope  of 
the  main  Santa  Lucia  ridge,  and  covers  the  headwaters  of  the 
north  fork  of  Santa  Rosa  Creek,  Cooper  Creek,  and  Oceanic 
Creek  (the  three  northern  forks  of  Santa  Rosa  Creek)  and  the 
divide  between  Santa  Rosa  and  San  Simeon  creeks  to  the  south 
fork  of  San  Simeon  Creek,  including  Sees.  8,  9,  10,  11,  12,  13, 
14,  15,  16,  17,  and  24,  T.  27  S.,  R.  9  E.,  and  Sees.  18  and  19, 
T.  27  S.,  R.  10  E.  The  geology  of  this  district  is  very  com- 
plicated. The  rocks  belong  almost  exclusively  to  the  Fran- 
ciscan series,  except  in  the  southeastern  corner,  where  the 
younger  formations  overlie  this  series. 

There  are  several  scattered  exposures  of  rhyolite  in  this 
district,  which  apparently,  however,  have  no  relation  to  the 
location  of  the  ore  deposits.  There  are  very  clearh-  defined 
lines  of  croppings.  having  a  northwestern  direction;  one.  start- 


152  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

ing  in  the  Vulture  mine,  crosses  the  divide  and  runs  through 
a  part  of  Cooper  Creek  basin;  another,  starting  southwest 
thereof,  crosses  the  divide  between  Cooper  and  Oceanic  creeks, 
on  the  ground  of  the  Oceanic  No.  2  mine,  and  runs  through 
the  Oceanic  mine.  A  third  line  of  croppings  lies  northeast  of 
the  latter,  and  may  be  those  of  a  second  or  back  ledge  found 
formerly  in  the  old  works  of  tunnel  No.  4  and  below  in  the 
upper  shaft  levels  of  the  Oceanic  mine.  These  croppings  go 
some  distance  farther  northwest,  but  do  not  reach  the  divide 
between  Santa  Rosa  and  San  Simeon  creeks.  On  this  divide  a 
ver}^  bold  line  of  croppings  starts  northward,  forming  a  con- 
tiguous line  of  bluffs  about  a  quarter  of  a  mile  long,  flanked 
on  both  sides  by  serpentine,  which,  however,  appear  not  to 
carry  any  cinnabar.  The  principal  material  of  the  croppings 
is  a  rather  light  gray,  flinty  quartz. 

The  principal  rocks  exposed  at  the  surface  are,  besides  the 
rhyolite  above  mentioned,  sandstone,  shales,  some  chert,  and 
occasionally  some  serpentine.  The  sandstone  is  generally 
much  decomposed,  with  a  brownish  or  greenish  gray  color,  but 
not  nearly  as  much  silicified  as  in  the  Adelaide  district.  The 
deep  erosions  and  the  fact  that  the  country  is  continually  slid- 
ing, lead  to  the  supposition  that  a  large  part  of  the  underlying 
rock  is  more  or  less  serpentinized,  which  is  confirmed  by  the  fact 
that  in  most  of  the  gulches  the  hard  sandstone  is  found  under- 
laid b}"  shales  or  serpentine. 

In  the  Lehman  property  the  younger  sandstones  are  found 
impregnated  with  cinnabar  in  close  vicinity  to  the  rocks  of  the 
Franciscan  series,  which  would  tend  to  show  that  the  period  of 
ore  format  on  was  posterior  to  that  of  the  deposition  of  those 
Upper  Cretaceous  or  Eocene  rocks.  As  this  deposition  was 
contemporaneous  with,  or  closely  following,  a  strong  process  of 
silicification,  the  highly  siliceous  character  of  the  ledge  matter 
of  most  of  the  mines  is  readily  explained,  the  Franciscan  series 
having  already  undergone  a  prior  process  of  silicification. 

Pine  Mountain  District. — This  district  is  characterized  by  the 
great  amount  of  exposures  of  rhj'olite.  These  rocks  are  lying 
in  a  series  of  prominent  knolls,  the  debris  covering  such  wide 
territory  that  it  is  impossible  to  give  any  estimate  of  the  width 
of  the  belt,  which,  however,  is  certainly  from  100  to  400  yards 
wide.     The  outcrops  are  not  continuous,  but  are  separated  by 


SAN    LUIS   OBISPO   COUNTY.  153 

short  exposures  of  the  Franciscan  series.  To  the  west  lies 
a  wide  belt  of  serpentine,  which  rock  only  shows  to  the  east 
in  the  territory  of  the  Pine  Mountain  group.  The  entire 
western  slope  of  the  main  ridge  and  that  part  of  the  eastern 
where  the  serpentine  occurs,  show  extensive  slides.  Near 
Rocky  Butte,  the  Chico  sandstone  lies  quite  close  to  the  igneous 
rocks.  The  enormous  amount  of  debris  prevents  the  obser\-a- 
tion  of  any  contact  metamorphic  phenomena.  Some  bowlders 
of  diorite  are  found,  but  none  in  place.  The  location  of  these 
bowlders  would  sviggest  that  the  vents  through  which  the 
rhyolite  was  ejected  were  old  lines  of  fracturing.  The  ore 
deposits  are  all  very  close  and  more  or  less  parallel,  but  not, 
as  far  as  yet  developed,  in  direct  contact  with  the  igneous  rocks. 

San  Carpoio  District. — This  district,  in  the  extreme  north- 
western corner  of  the  county,  includes  part  of  Monterey 
Count}'.  This  countrj^  is  very  deeply  eroded  and  the  sidehills 
are  ver}^  steep.  The  country  between  San  Carpojo  Creek  and 
the  ocean  is  prominently  a  highly  silicified  Franciscan  sand- 
stone. To  the  east  of  the  creek  and  forming  the  backbone  of 
the  main  ridge  is  a  wide  belt  of  serpentine,  along  which,  on 
its  western  line,  runs  a  belt  of  croppings,  which,  it  is  claimed, 
can  be  traced  from  Pine  Mountain  to  the  northern  watershed 
of  Salmon  Creek,  where  cinnabar  has  been  found  in  these 
croppings.  In  the  basin  forming  the  headwaters  of  the  west 
fork  of  San  Carpojo  Creek  runs  a  minor,  more  local,  parallel 
belt  of  serpentine,  west  of  which  are  the  croppings  on  which 
the  Dutro  mine  is  found,  and  on  the  ocean  slope  detached 
patches  of  serpentine  can  be  found.  There  are  through  this 
country,  besides  the  cinnabar  outcrops,  several  outcrops  of  gold 
ore,  on  some  of  which  prospecting  is  being  done. 

The  Adelaide  and  Oceanic  districts  are  not  very  well  tim- 
bered. On  Cypress  Mountain  some  durable  cypress  mine- 
timber  can  be  found,  and  to  the  north  thereof  there  is  some 
good  pine  timber.  The  amount  of  available  fuel  is  also 
restricted.  The  Pine  Mountain  district  is  better  provided  with 
timber.  The  Pine  Mountain  mine  is  equipped  with  a  small 
sawmill,  and  there  is  considerable  fuel  timber  in  this  district. 
The  cost  of  timber  in  the  Adelaide  district  is :  round  timber, 
7  cents  per  linear  foot ;  lagging,  6  cents  apiece ;  cordwood, 
$3.25    per   cord.     In  the  Oceanic  district,  round  timber,    3^ 


154  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

cents  per  linear  foot,  to  which  must  be  added  $8  per  load  for 
hauling;  lagging,  ^j4  cents  apiece;  sawed  timber,  $15  per 
1000  feet  (B.  M.);  cordwood  (pine),  $4  per  cord. 

The  Adelaide  district  connects  with  the  railroad  at  Paso 
Robles,  distant  from  1 6  to  20  miles.  For  the  southern  part  of  the 
district  steamship  connection  is  made  at  Ca3'UCOs,  distant  about 
12  miles.  The  Oceanic  district  is  from  16  to  19  miles  from  San 
Simeon,  another  steamship  shipping  point.  The  Pine  Moun- 
tain district  is  about  10  miles  distant  from  San  Simeon. 

Alice  and  Modoc  Group. — This  lies  in  Adelaide  District,  in  Sec. 
17,  T.  27  S.,  R.  10  E.  California  Consolidated  Mining  Com- 
pany, owner;  Wm.  A.  Stuart,  No.  606  Montgomer}-  street,  San 
Francisco.  There  are  most  probabh-  two  separate  ore  deposits 
in  this  property.  [See  Fig.  52.]  One,  having  a  course  X.  50° 
E.,  and  a  southeasterly  dip,  is  worked  from  the  surface  down 
to  a  drift  (n)  75  feet  deeper  (vertical),  and  showing  there  over 
a  length  of  40  feet  on  the  strike,  the  ore  bod\'  going  farther  at 
both  ends.  The  width  of  the  ore  body  is  certainly  S  feet,  but 
the  roof  is  still  in  ore.  From  this  level  an  understope  35  feet 
deep  on  an  incline  of  about  45°  is  in  progress.  Another  ore 
body,  having  a  course  N.  70"^  E.,  and  a  southeasterly  dip,  lies 
about  200  feet  south  of  the  former.  It  is  opened  from  the  sur- 
face to  a  level  (/?)  30  feet  (vertical)  lower,  where  it  is  worked 
out  to  a  length  of  at  least  60  feet  on  the  strike,  and  a  width  of 
from  6  to  7  feet.  Below  this  level  it  has  been  partially  worked, 
and  a  chute  connects  this  work  with  the  lowest  tunnel  (c), 
which  is  on  a  level  with  the  retort,  and  215  feet  vertical  below 
the  upper  works.  At  the  point  where  the  chute  connects  with 
this  tunnel,  583  feet  from  mouth,  the  course  of  the  ore  body  is 
nearly  east  and  west,  dip  south.  The  same  ore  body  is  cut  by 
the  tunnel  460  feet  from  mouth,  showing  a  width  of  10  feet, 
and  standing  nearly  vertical.  The  propertj'  is  equipped  with 
two  i2-pipe  retort  furnaces. 

Bank  Mine. — Pine  Mountain  District.  In  Sec.  36,  T.  26  S., 
R.  8  E.  E.  S.  Rigdon,  of  Cambria,  owner.  The  country  rock 
of  this  property  is  entirely  serpentine;  the  ledge  matter  is  a 
highly  silicified  serpentine,  carrying  cinnabar,  which  latter  is 
also  sparingly  disseminated  through  the  adjacent  serpentine 
wall  material.     The  tunnel  was  caved  and  inaccessible.     The 


SAN    LUIS   OBISPO    COUNTY. 


155 


156  QUICKSILVER    RESOURCES   OP   CALIFORNIA. 

croppings  indicate  a  very  flat  ledge,  strike  nearly  east,  dip  north, 
which  is  well  charged  with  cinnabar. 

Cypress  Mountain  Group. — Adelaide  District.  In  Sees,  i  and  2, 
T.  27  S.,  R.  9  E.  J.  H.  Follis,  of  San  Francisco,  and  E.  Smith 
and  W.  S.  Forrington,  of  Paso  Robles,  owners.  This  group  of 
mines  is  located  near  the  only  exposure  of  igneous  rocks 
appearing  in  this  district,  and  near  the  prominent  serpentine 
exposure  of  Cypress  Mountain.  The  dike  of  rhyolite,  about 
three  quarters  of  a  mile  long  and  800  feet  wide,  runs  about 
N.  30°  W.  On  the  west  side  lies  a  readily  traceable  line  of 
croppings,  which  has,  however,  onl}^  been  superficially  opened 
at  one  point,  in  the  northwest  corner  of  section  i,  by  the 
Columbia  tunnel;  the  material  taken  out  of  this  tunnel  pros- 
pects ver\'  fairly  in  cinnabar.  Most  of  the  work  has  been  done 
on  the  northeast  side  of  the  rhj'olite  dike;  on  this  side  the 
croppings  are  not  very  plain,  and  scattered.  In  one  tunnel  an 
ore  body  has  been  cut  about  10  feet  wide,  in  a  black  claj-  gouge 
with  sandstone  bowlders;  whether  a  ledge  or  a  lens  of  ore  can 
not  be  stated.  On  the  hanging  wall,  but  apparently  belonging 
to  the  ledge  filling,  is  a  stratum  of  chert}^  quartz  about  12 
inches  thick. 

Doty  Mines. — Pine  Mountain  District.  This  property  com- 
prises five  claims  lying  adjacent  to  the  northwest  of  the  Quien 
Sabe  mines,  in  Sec.  14,  T.  26  S.,  R.  8  E.  Doty  Brothers,  of 
Cambria,  owners.  The  lower  tunnel,  about  75  feet  above  the 
creek  level,  is  inaccessible.  Judging  from  the  dump  the  ore 
deposit  is  formed  in  highh'  silicified  serpentine.  Some  of  the 
quartz  seams  have  in  their  center  a  verj^  narrow  seam  of  cin- 
nabar; in  other  samples  the  cinnabar  forms  in  the  center  of 
quartz  bunches,  indicating  that  the  cinnabar  deposition  is  con- 
nected with  the  silica  formation,  but  posterior  to  the  latter. 
A  short  tunnel,  25  feet  above  the  lower  tunnel  cuts  very  near 
the  entrance,  a  ledge  having  a  course  nearly  east  and  west, 
about  20  feet  between  walls.  The  hanging  wall  is  a  very 
coarse  sandstone.  The  gouge  is  very  solid,  the  dip  nearly  ver- 
tical. The  foot  wall,  while  too  near  the  surface  to  be  abso- 
lutel)'  determined,  is  probably  shale,  the  foot-wall  gouge 
being  much  softer;  its  dip  is  verj^  flat,  nearing  the  hanging 
wall  on  the  dip. 


SAN    LUIS   OBISPO   COUNTY.  157 

Elizabeth  Mine.— Adelaide  District.  In  Sec.  17,  T.  27  S., 
R.  10  E.  H.  Eppinger,  of  San  Francisco,  owner.  This 
property  lies  adjacent  to  the  Alice  and  Modoc,  on  a  line 
of  croppings  running  N.  30°  W.  Some  surface  openings 
show  that  bunches  of  ore  have  been  taken  out.  The  rocks 
show  some  signs  of  cinnabar.  A  crosscut  tunnel,  running 
east  toward  these  croppings,  was  inaccessible.  The  dump 
showed  nothing  except  cla3'ey  material.  Another  tunnel,  run- 
ning from  the  road  in  a  southeasterly  direction,  about  east  of 
the  retort,  was  also  inaccessible.  The  property  is  equipped 
with  a  lo-pipe  retort  furnace. 

Eureka  Group. — Adelaide  District.  In  Sees.  6  and  7,  T.  27  S., 
R.  10  E.,  and  Sees,  i  and  12,  T.  27  S.,  R.  9  E.  Mr.  R.  Wear, 
of  Paso  Robles,  owner. 

George  and  Josephine  Group. — Adelaide  District.  In  Sees.  i8 
and  20,  T.  27  S.,  R.  10  E.  L.  G.  Sinnard,  of  Paso  Robles,  and 
J.  Tartaglia,  of  Klau,  owners.  [See  Report  State  Mining  Bu- 
reau of  Cal.,  X,  page  580.]  This  group  lies  between  the  Alice 
and  Modoc  and  the  Ea  Eibertad  mines,  and  shows  some  surface 
croppings  and  some  shallow  tunnels.  When  formerly  worked 
a  small  furnace  was  erected  on  the  property.  The  old  works 
are  inaccessible. 

Karl  Mine.— Adelaide  District.  In  Sec.  33,  T.  26  S.,  R.  10  E. 
The  Karl  Quicksilver  Mining  Company,  owner;  J.  Bagbj-,  of 
Klau,  San  Euis  Obispo  County,  superintendent.  A  line  of 
croppings  runs  through  this  property,  entering  it  in  the  south- 
western part  on  an  east  and  west  course,  but  turning  very 
shortl}'  after  entering  the  propert}'  to  a  southeastern  direction. 
The  character  of  the  croppings  also  changes  a  little,  in  so  far 
as  they  get  a  little  less  ochery  than  at  their  point  of  entrance. 
The  workable  ore  bodies  have  been  exclusively  developed  in 
the  southeastern  part  of  the  propert}-.  A  great  amount  of 
open  cuts  and  extensive  underground  works  have  been  made. 
The  company  has  developed  two  principal  ledges,  running 
nearly  parallel  N.  50^  W.,  dipping  northeast,  but  approaching 
each  other  on  the  dip.  The  most  southwestern  ledge  is  localh- 
called  the  serpentine  ledge.  Its  foot  wall  is  a  belt  of  serpen- 
tine from  20  to  40  feet  wide,  rather  siliceous  in  places,  as  in 
the  tunnel  wherein  the  shaft  is  located,  taking  a  chalcedonic 


158  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

character;  this  serpentine,  however,  does  not  appear  at  the 
surface,  but  is  capped  to  a  depth  of  from  20  to  30  feet  by  the 
croppings  of  the  gouge  accompanying  the  ore  deposit.  The 
ledge  matter  of  the  serpentine  ledge  is  a  loose,  coarsely-granu- 
lated quartz,  carrying  iron  and  mercury  sulphides.  The  entire 
mass  has  a  grayish-green  color.  Under  the  glass  scarcely  a 
trace  of  serpentine  can  be  found  among  the  granules.  The 
color  is  given  by  the  accompanying  clay,  which  must  be  derived 
from  the  serpentine.  In  this  loosely-granulated  quartz  are 
found  bowlders  of  a  very  hard  chalcedonic  quartz  and  of  a 
laminated,  somewhat  calcareous  material.  Some  of  the  bowl- 
ders carry  sensible  amounts  of  cinnabar  and  pyrite;  others  are 
entirely  barren,  and  their  relation  to  the  surrounding  country 
rock  is  not  clear.  The  hanging-wall  material  of  this  ledge, 
which  forms  also  the  foot  wall  of  the  second  ledge  above  men- 
tioned, is  a  slightly  metamorphosed  sandstone.  Immediatel}^ 
on  the  ledge  lies  a  heavy  claj-,  colored  green  probably  by  sul- 
phate of  iron.  The  parallel  ledge  forms  in  a  zone  of  what 
appears  to  be  a  crushed  country  rock,  probably  of  a  quartzose 
character,  but  having  some  clay  in  it,  probably  as  a  result  of 
the  attrition.  The  ore  contains  considerable  iron  pyrite  and 
some  free  sulphur. 

Both  these  ledges  are  well  developed  in  the  incline  shaft 
sunk  from  tunnel  No.  i,  at  an  angle  of  60°,  to  a  depth  of  155 
feet  from  the  level  of  the  tunnel.  The  collar  of  the  shaft  is 
125  feet  below  the  surface.  There  are  wide  stopes  in  the  ser- 
pentine ledge  above  the  lower  level,  and  the  parallel  ledge  is 
also  opened,  showing  clearl}-  the  difference  in  character  of  the 
two  ore  bodies,  which,  however,  in  this  level  are  much  closer 
together  than  at  the  surface..  The  strike  of  the  ledges  in  the 
lower,  or  No.  3,  level  is  N.  45°  W.;  the  average  dip  is  N.E.  45". 
Crosscutting  in  the  same  level  in  a  direction  N.  35"^  E. 
from  shaft  about  100  feet,  the  parallel  ledge  above  mentioned 
is  cut,  showing  also  important  ore  bodies.  The  foot  wall  of 
the  ore  zone  is  a  chalcedonic  material,  probably  serpentine 
altered  by  silicification,  and  colored  green  by  sulphate  of  iron. 
This  is  underlaid  bj'  a  dark-gray  indurated  clay  mixed  with  a 
lighter,  grayish-colored  sandstone. 

A  great  part  of  the  product  of  this  mine  has  been  derived 
from  large  open  cuts.     At  present,  however,  the  main  ore  sup- 


SAX    LUIS    OBISPO    COUNTY. 


159 


ply  comes  from  the  works  in  tunnel  No.  i.  The  furnace  is  an 
8-tile  Scott  fine-ore  furnace,  with  fourteen  brick  condensers 
and  ten  stave  barrel  condensers. 

Kismet  Group. — Adelaide  District.  In  Sec.  7,  T.  27  S., 
R.  ID  E.  F.  D.  Frost  and  E.  Smith,  of  Paso  Robles,  owners. 
The  group  comprises  the  Kismet,  Margaret,  and  Alice  C. 
claims.  A  short  tunnel  on  the  Alice  C.  claim  shows  some 
cinnabar-carrying  rock  near  the  mouth. 


PHOTO  No.  U.     I-.\  LII!ERT.\D  MINE. 

La  Libertad  Mine. — Adelaide  District.  In  Sec.  21,  T.  27  S., 
R.  10  E.  Libertad  Quicksilver  Mining  Company  (G.  A. 
Trafton,  of  Watsonville,  Santa  Cruz  County,  president),  lessee  ; 
owner,  D.  McEwen,  Cambria,  San  Luis  Obispo  County.  This 
mine  is  located  on  the  contact  of  a  prominent  belt  of  serpen- 
tine and  a  sandstone  belonging  to  the  metamorphic  series. 
The  general  trend  of  the  croppings  is  northwest.  While  the 
croppings  would  indicate  a  regular  strike  of  the  ledge,  the 
underground  works  have  as  yet  only  developed  ore  bodies  hav- 


160 


QUICKSILVER   RESOURCES    OF   CALIFORNIA. 


ing  difierent  strikes  and  dips,  which  latter  are,  however,  all 
eastward  or  in  the  hill,  as  the  accompanying  sketch  of  tunnel 
No.  2  will  indicate.  [See  Fig.  53.]  These  ore  bodies  lie  in  a 
dark- gray  indurated  clay,  intermingled  with  a  great  number 
of  sandstone  bowlders  carrying  some  serpentine.  This  material 
appears  to  be  the  contact  zone  of  the  sandstone  and  serpentine. 
The  ore  bodies  are  formed  by  rather  hard  quartzose  bodies  of 
a  whitish  color,  having  small  serpentine  inclusions,  the  cinna- 


N 

LIBERTAD 

' 

' 

*^^             ^0                             TUNNEL    No.  2.           1 

"^•^                                    Elev.  =   /eso' 

//     * 

0 

K        *^ 

<>-         » 

top 

#                "^  E           ^fope /o  sur/ace 

(^.\  ^-i^i^  Ve  r  t  i  c  0  I    Shaft 

^<$b^                  50' 

^  Ip            yy'^ 

^^:^'Tf- 

¥^  y^ 

J^WOre  ,n  # 

hx          ^^S!^ 

yy^=iS^^^^ 

+■> 

jy'^ 

^■0 

y^ 

^2> 

^^ 

*^       ' 

Ay/^ 

+^ 

^r 

rccT 

0                   as 

so 

-<; 

V 

^ 

bar  forming  principally  in  the  seams,  sometimes  one  fourth  of 
an  inch  wide,  in  a  crystalline  form. 

Following  about  the  same  southeasterly  strike,  the  croppings 
can  be  traced,  until  about  a  quarter  of  a  mile  below  the  retort 
the  ledge  crosses  the  creek,  where  the  exposure  shows  the 
ledge  with  a  width  of  from  8  to  10  feet,  having  a  very  rich 
streak  from  6  to  8  inches  wide,  carrying  metacinnabarite  asso- 
ciated with  the  cinnabar;  course  N.  50°  \V.,  dip  northeast;  the 
ledge  matter  being  prominently  of  a  flinty  character,  and  with 
a  sandstone  foot  wall.  The  ledge  in  its  southeasterly  strike 
diverges  from  the  serpentine  and  is  entirely  in  the  sandstone. 


SAN    LUIS   OBISPO    COUNTY.  161 

This  exposure  is  loo  feet  below  the  bottom  of  the  shaft  in 
tunnel  No.  2,  the  lowest  ore  exposure  in  the  northwestern  part 
of  the  property,  and  distant  therefrom  about  1500  feet  in  an 
air  line. 

Southwest  of  the  creek,  the  ledge  crops  out  again.  Panning 
from  the  dirt  showed  here  free  mercury,  which  does  not  show 
on  the  northeast  side  of  the  creek.  The  mine  is  equipped  with 
a  lo-pipe  retort  furnace. 

Lehman  Mine. — Oceanic  District.  In  Sec.  13,  T.  27  S.,  R.  9  E. 
F.  Lehman,  of  Cambria,  owner.  This  is  in  the  Upper  Cre- 
taceous or  Eocene  sandst6ne;  this  sandstone  is  a  white,  fine- 
grained material,  with  conchoidal  fracture;  when  broken  the 
fracture  planes  have  a  black  color  and  emit  a  bituminous  odor. 
Strike  nearly  east  and  west,  dip  S.  30°.  In  the  seams  of  this 
rock  is  a  dolomitic  gangue,  carrj'ing  some  cinnabar.  The 
developments  consist  of  a  tunnel  40  feet  long,  about  200  feet 
below  top  of  ridge,  and  a  couple  of  shallow  open  cuts. 

Madrone  Mine. — Adelaide  District.  In  Sec.  22,  T.  27  S.,R.  loE. 
Madrone  Quicksilver  Mining  Company, owner,  233  S.Broadway, 
Los  Angeles.  The  development  on  this  property  consists 
entirely  of  surface  work;  the  deepest  accessible  point  is  not 
over  25  feet  below  the  surface.  These  surface  works  show 
very  good  ore,  and  in  one  place  a  well-defined  vein,  running 
nearly  east  and  west  and  dipping  very  steep  northward.  The 
hanging-wall  material  could  not  be  determined.  It  carries  in 
places  sensible  amounts  of  bitumen.  Next  to  the  hanging 
wall  occurs  a  hard  flinty  material  carr\'ing  some  cinnabar;  then 
comes  softer  ochreous  rock,  in  places  ver>'  rich  in  cinnabar; 
and  then  a  breccia  on  the  foot  wall,  carrs-ing  some  cinnabar. 
The  foot  wall  is  the  indurated  grayish  clay  and  sandstone 
bowlders  found  in  all  the  mines  in  the  vicinity.  The  property 
is  equipped  with  a  lo-pipe  retort  furnace. 

Mahoney  (Buena  Vista  or  Gould)  Mine.— Adelaide  District.  In 
Sec.  33,  T.  26  S.,  R.  10  E.  J.  J.  O'Toole,  Parrott  Building,  San 
Francisco,  owner;  A.  Gould  and  G.  Bell,  of  Klau,  San  Luis 
Obispo  County,  lessees.  This  mine  lies  east  of  and  adjacent 
to  the  Karl,  and  very  close  to  the  Chico  sandstone,  which  east 
and  southeast  of  it  apparently  overlies  the  Franciscan  series. 
Considerable  work  has  been  done  in  former  times,  and  also  by 


162  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

the  present  lessees,  but  no  regular  formation,  either  of  ore 
deposition  or  of  country  rock,  has  as  j'et  been  developed.  The 
ore  is  scattered  in  bunches  through  a  partially  indurated  clay 
material  mixed  with  sandstone  bowlders,  verj'  similar  in  char- 
acter to  the  foot  wall  of  the  ore  zone  in  the  Karl.  Some  of 
these  ore  bodies  are  of  considerable  size  (one  400  feet  in  from 
tunnel  No.  i  was  from  10  to  15  feet  wide  and  about  30  feet 
high),  but  they  are  without  an}-  regularity  of  arrangement. 
This  property  is  equipped  with  a  lo-pipe  retort  furnace. 

North  Star  Mine  (formerly  Santa  Maria). — San  Carpojo  Dis- 
trict. In  Sec.  13,  T.  25  S.,  R.  6  E.  William  Gillespie  and 
J.  H.  Ailing,  of  San  Simeon,  owners.  It  lies  to  the  southeast 
of  the  Polar  Star. 

Oceanic  Mine. — Oceanic  District.  In  Sees.  15  and  21,  T.  27  S., 
R.  9  E.  Oceanic  Quicksilver  Company,  owner,  No.  2  Baker 
Block,  Los  Angeles;  A.  B.  Thomas,  president;  E.  W.  Carson, 
of  Cambria,  superintendent.  [See  Report  State  Mining  Bureau 
of  Cal.,  VIII,  page  531;  X,  page  5S0;  XII,  page  366.] 

This  mine  was  actively  operated  from  1876  to  1879,  and  pro- 
duced 7400  flasks  of  quicksilver  in  that  period.  The  mine  was 
onl}'  sporadically  worked  from  that  time  until  the  present  com- 
pany came  into  possession.  The  latter  has  reopened  the  mine 
and  just  completed  a  Scott  fine-ore  furnace  with  a  minimum 
daily  capacity  of  60  tons. 

The  development  of  this  mine  has  been  done  partly  by  open 
cuts  and  partly  by  underground  work.  From  the  surface  work- 
ings large  bodies  of  ore  have  been  worked  out,  their  general 
strike  being  N.  55°  W.,  dipping  southwest.  The  ore  bodies 
show  considerable  width,  and  their  faces  show  that  consider- 
able ore  is  yet  available  for  surface  work,  carn'ing  sufficient 
cinnabar  to  be  considered  satisfactory  furnace  material.  The 
underground  works  consist  of  several  tunnels;  the  lowest  tun- 
nel. No.  4,  cuts  the  vein  at  a  depth  of  250  feet  below  the  sur- 
face. From  this  level  a  shaft  has  been  sunk  on  the  vein.  The 
lowest  level  at  present  in  operation  in  this  shaft  is  185  feet 
below  the  level  of  tunnel  No.  4.  The  vein  changes  its  dip  to 
the  northeast  about  100  feet  below  the  level  of  the  tunnel.  The 
dip,  how-ever,  is  nearly  vertical.  The  strike  of  the  vein  is 
N.  60°  W.  The  southern,  or  foot  wall  is  a  shale  "mudrock," 
which  material  is  rather  prominent  in  the  neighborhood  of  this 


SAN    LUIS   OBISPO   COUNTY.  163 

mine  and  is  very  similar  to  the  "mudrock"  in  the  Manhattan 
and  other  mines.  The  real  hanging,  or  northern,  wall  has  not 
been  reached  in  the  underground  works.  On  the  ledge  matter 
lies  a  belt  of  black  clay,  with  inclusions  of  harder  material  very 
similar  to  that  composing  the  foot  wall.  A  crosscut  lOO  feet 
in  length  in  the  185-foot  drift  has  not  cut  through  this  clay 
selvage.  The  ledge  matter  proper  (or  the  matrix  wherein  the 
ore  makes)  is  a  coarse  grayish  sandstone,  rather  compact, 
through  which  aggregates  of  cinnabar  crystals  and  iron  sul- 
phide crystals  are  disseminated,  the  cinnabar  not  being  con- 
fined to  seams  in  the  sandstone.  The  sandstone  slakes  very 
sensibh^  when  exposed  to  the  air,  and  carries  some  lime.  These 
bodies  of  sandstone  are  rather  close  to  the  hanging  wall.  They 
are  inclosed  in  the  black  clay,  are  not  continuous,  and  lie  with- 
out any  regularity  in  the  fissure,  nor  is  the  sandstone  persist- 
ently ore-bearing.  As  far  as  observed,  they  are  not  connected, 
although  it  is  not  improbable  that  such  is  the  case,  as  the  clay 
can  hardl}'  have  been  the  channel  for  the  mineral-carrying 
solutions;  they  must  have  found  their  channel  in  the  less 
imper\-ious  sandstone. 

Oceanic  No.  2. — Oceanic  District.  In  Sec.  ii,  T.  27  S., 
R.  9  E.  F.  Lehman,  of  Cambria,  owner.  This  property  is 
located  on  the  ridge  between  Cooper  and  Oceanic  creeks,  on  a 
line  of  croppings  running  toward  the  Oceanic  ground.  There 
are  some  old  tunnels,  which  are  caved  in. 

Pine  Mountain  Group. — Pine  Mountain  District.  Consists  of  a 
group  of  twenty-two  mining  claims  and  several  tracts  of  tim- 
ber land  situated  on  and  around  Pine  Mountain,  mostly  on  the 
east  slope  of  the  mountain,  in  Sees.  3,  10,  and  11,  T.  26  S., 
R.  8  E.  The  American  Exploration  and  Development  Com- 
pany, owner;  M.  Hoytema,  care  Jabish  Clement,  No.  212  San- 
some  street,  San  Francisco,  and  San  Simeon,  San  Luis  Obispo 
County,  general  manager.  [See  Report  State  Mining  Bureau 
of  Cal.,  \'III,  page  531;  X,  page  580;  X,  page  581 — Ocean 
View.] 

The  principal  workings  are  situated  on  the  east  side  of  the 
body  of  rhyolite  forming  Pine  Mountain,  which  is  the  most 
southern  of  three  eruptive  cones,  verj'  close  together,  but  not 
connected  and  of  slightly  varying  material,  lying  along  the 
backbone  of  the  main  ridge.     The  igneous  rock  has  covered  a 

II— (2R 


164 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


large  territory  on  both  sides  with  debris.  The  country  rock 
belongs  to  the  Franciscan  series — shale,  sandstone,  and  ser- 
pentine, the  latter  principally  on  the  coast  slope  and  in  the 
southern  part  of  the  property  from  the  Pine  Mountain  tunnel 
to  the  Little  Almaden.     East  of  the  rh3'olite  of  Pine  Mountain, 

a   line  of   croppings    can 
be  traced  along  the  foot 
^  of     the     main     eruptive 

<*?  body,  but  has,    in    many 

''       ^^  places,  slid  down  the  hill- 
side.   Most  of  the  work- 
^  '^  ings  in  the  Bucke^-e,  Little 

Almaden,     and     possibly 
the    Pine   Mountain,    are 
located  on  such  slides,  but 
the  Ocean  View  tunnel  probabh-  cuts 
the  ledge  in  place. 

The  main  workings  are  :  The  Ocean 
View  lower  tunnel,  just  below  the 
camp,  1300  feet  long,  still  in  progress 
of  drifting.  The  course  of  the  tunnel 
is  S.  25°  W.  [see  Fig.  54] ;  the  first 
400  feet  are  in  shale  and  a  black  clay 
gouge,  then  come  10  feet  of  rhyolite. 
An  upraise  leads  here  to  a  short  drift 
15  feet  above  the  tunnel  level,  show- 
ing some  ore  in  a  serpentine  quartzose 
material.  The  main  tunnel  con- 
tinues in  this  latter  material  to  610 
feet  from  entrance,  then  to  7S6  feet 
in  black  cla}^  gouge,  where  it  cross- 
cuts the  main  ledge  on  a  very  obtuse 
angle.  The  course  of  the  ledge  is 
nearly  south,  dipping  east.  The  material  is  a  flinty  quartz, 
stained  in  places  grayish-green  by  silicate  of  iron.  The  cin- 
nabar occurs  principally  as  paint,  especialh"  in  bunches.  Past 
this  ledge  to  the  breast  the  tunnel  is  in  black  gouge.  Above 
the  level  of  this  tunnel  considerable  work  has  been  done.  A 
winze  runs  up  65  feet  and  two  levels  have  been  run  above  the 
tunnel  level.     There  are  also  two  old  upper  tunnels.     Out  of 


'2815 

Fig.  54.  Lower  Ocean  View 
tunnel,  Pine  Moun- 
tain Mine. 


SAN   LUIS   OBISPO   COUNTY.  165 

these  works  ore  has  been  taken  and  treated  in  the  pipe  retort 
furnace. 

On  the  Buckej-e  a  shaft  has  been  sunk  on  verj'  good  crop- 
pings,  and  a  drift  350  feet  long,  S.  76°  W.,  has  been  run,  which 
connects  with  the  bottom  of  the  shaft  at  a  depth  of  78  feet,  300 
feet  from  the  entrance.  The  ore  at  the  lower  level  is  a  flinty 
quartz.  The  surface  is  covered  with  rh3'olite  bowlders.  The 
tunnel  shows  that  the  country  is  shale,  and  for  the  last  200  feet 
serpentine.  This  work  is,  however,  most  probably  in  a  slide 
from  the  main  body. 

On  the  Pine  Mountain  a  tunnel  running  nearly  west  is  300 
feet  long.  The  countrj^  rock  is  serpentine.  The  tunnel  is 
inaccessible.  Judging  from  the  dump,  the  tunnel  has  cut 
serpentine  and  in  the  face  shale. 

The  lyittle  Almaden  is  an  open  cut.  Work  has  been  done  on 
a  large  body  of  croppings  in  a  body  of  serpentine,  which  shows 
clearly  evidence  of  sliding. 

Polar  Star  Mine  (also  called  Santa  Clara,  or  Black  Hawk). — 
San  Carpojo  District.  In  Sec.  13,  T.  25  S.,  R.  6  E.  Owners, 
Public  Administrator,  G.  E.  Van  Gordon,  E.  S.  Rigdon,  M.  W. 
Minor,  and  R.  A.  Minor,  of  Cambria;  S.  N.  Hitchcock,  C.  D. 
Hitchcock,  F.  H.  Little,  and  W.  Eittle,  of  San  Simeon;  H.  H. 
Carpenter,  of  San  Luis  Obispo;  P.  A.  H.  Arate,  of  San  Luis 
Obispo.  [See  Report  State  Mining  Bureau  of  Cal.,  X,  page 
581;  XII,  page  366 — Black  Hawk.]  This  is  an  old  mine;  it 
has  been  worked  sporadically  since  1870  by  different  owners. 
There  is  a  great  amount  of  surface  ore  on  the  south  side- 
hill  of  San  Carpojo  Creek,  covering  near  the  creek  a  distance 
of  250  feet,  running  750  feet  up  the  hillside  and  narrowing  to 
about  40  feet  at  an  altitude  of  310  feet  vertically  above  the 
creek;  this  surface  zone  is  from  6  to  20  feet  deep.  \^ery  rich 
ore  has  been  found  in  this  territorj^  but  as  yet  the  vein  has 
not  been  exposed.  Some  exposures  of  what  is  probably  the 
southern  wall  would  indicate  that  the  vein  had  an  east  and 
west  trend.  The  country  rock  is  almost  exclusively  highly 
silicified  Franciscan  sandstone.  The  property  is  equipped  with 
a  two  Q  retort  furnace  in  good  order. 

Quien  Sabe  Mine. — Pine  Mountain  District.  Contains  three 
claims;  Ouien  Sabe  Nos.  i,  2,  and  3,  in  Sec.  14,  T.  26  S., 
R.  8  E.     G.  E.  Van  Gordon  and  M.   W.  Minor,   of  Cambria, 


166  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

owners.  The  line  of  these  claims  is  in  a  northwestern  direction. 
All  the  work  has  been  done  on  the  northeastern  claim,  which 
abuts  with  its  north  end  line  against  one  of  the  branches  of 
the  Arroyo  del  Pinal.  The  igneous  rocks  of  Rock}-  Butte  lie 
very  close  and  parallel  to  the  east  side  line.  The  intervening 
space  is  in  Franciscan  sandstone.  The  two  eastern  claims  are 
located  so  as  to  cover  a  ridge  of  serpentine,  having  sandstone 
on  both  sides.  On  both  contacts  are  lines  of  croppings,  charged 
with  cinnabar.  Those  on  the  west  contact  of  the  serpentine 
are,  however,  the  more  prominent.  An  open  cut  on  the  west- 
ern croppings  shows  good  ore.  The  ledge  matter  is  flinty 
material.  Some  garnets  can  be  found  in  this  rock.  Both  cin- 
nabar and  metacinnabarite  occur  in  the  vein  matter.  On  the 
eastern  croppings  a  shaft  loo  feet  deep  has  been  sunk.  The 
character  of  the  ore  is  very  similar  to  that  of  the  western 
croppings.  From  the  creek  level  a  tunnel  has  been  started 
nearly  on  the  center  line  of  the  northeastern  claim.  This  tun- 
nel, 240  feet  long,  has  not  yet  reached  the  ore  deposit.  Its  face 
is  in  black  gouge,  with  inclusions  of  gra3'ish  sandstone  and 
igneous  rock.  At  a  distance  of  750  feet  it  will  be  under  the 
w^orks  above  described,  at  a  depth  of  230  feet. 

Rinconada  Mine. — In  Sees.  21  and  28,  T.  30  S.,  R.  14  E.  Mrs. 
Theresa  Bell,  of  San  Luis  Obispo,  owner.  [See  Report  State 
Mining  Bureau  of  Cal.,  X,  page  581;  XII,  page  366.]  This 
propert}'  consists  of  two  claims  and  two  millsites,  located  about 
12  miles  southeast  from  Santa  Margarita,  a  station  on  the 
Southern  Pacific  Railroad,  and  20  miles  from  San  Luis  Obispo. 
The  property  was  worked  from  1875  to  1883,  and  equipped 
with  two  furnaces — one  of  20  tons,  the  other  of  60  tons  capacity. 
It  was  shut  down  in  the  latter  j-ear  and  practicall}'-  abandoned. 
It  was  relocated  in  1897.  In  1898  a  lo-pipe  retort  furnace  was 
erected,  but  in  1901  the  then  owner,  Mr.  Petreida,  died,  and 
since  that  time  no  work  of  any  consequence  has  been  done  on 
the  property. 

The  country-  rock  is  almost  exclusively  serpentine.  Some 
shale  exposures  are  found  in  the  bed  of  a  creek  about  a  quarter 
of  a  mile  west  of  the  main  workings.  The  mine  is  located  in  a 
basin  formed  by  a  bend  of  the  mountain  ridge,  and  apparently 
filled  by  material  broken  ofi  the  ridge.  Through  this  basin 
runs  a  line  of  croppings  showing  very  boldly  in  the  northwest- 


SAN    LUIS   OBISPO    COUNTY.  167 

ern  part  of  the  Tenderfoot  claim  and  in  a  cliff  about  a  quarter  of 
a  mile  northwest  thereof,  the  entire  interv-ening  surface  being 
covered  b}^  large  bowlders  of  croppings.  Due  west  of  the  first 
named  place,  topographicallj-  above  this  line  of  croppings  in  a 
gulch,  croppings  are  also  found.  The  main  works  consist  of 
extensive  open  cuts,  principally  worked  in  the  70's,  with  short 
drifts  and  inclines — all  in  the  croppings;  a  j^ellow  ochery  mate- 
rial held  together  by  a  network  of  chalcedonic  quartz  seams. 
A  gulch,  course  N.  45"^  E.,  runs  at  the  northeastern  foot  of  the 
ridge  on  which  the  croppings  are  located,  and  three  tunnels 
have  been  run  under  these  croppings.  The  upper  tunnel  near 
the  head  of  the  gulch,  115  feet  below  the  top  of  the  ridge,  is 
caved  in.  Judging  from  the  dump  this  tunnel  was  run  in  ser- 
pentine and  shale.  Lower  down  the  gulch  is  another  short 
tunnel,  about  50  feet  long,  entirely  in  serpentine.  About  500 
feet  lower  down  in  the  gulch  and  about  under  the  northeast 
edge  of  the  croppings,  50  feet  lower  verticallj^  than  the  first 
tunnel,  is  the  third  tunnel,  running  south  about  200  feet,  then 
S.  35°  E.,  200  feet.  This  tunnel  is  in  serpentine.  The  breast 
is  at  the  contact  of  the  serpentine  and  the  sandstone.  About 
30  feet  from  the  breast,  short  crosscuts  have  been  run  on  a 
fissure,  having  on  the  southeast  wall  a  black  clay  gouge;  a 
shaft  or  winze  has  been  sunk  in  the  northeast  crosscut,  but  is 
covered  up  and  is  inaccessible.  The  country  in  the  neighbor- 
hood is  well  supplied  with  oak  timber  for  fuel  purposes,  but 
mining  timber  is  rather  scarce. 

Sunset  View  Quicksilver  Company. — San  Carpojo  District.  Con- 
sists of  a  cluster  of  mines  in  Sees.  13  and  18,  T.  25  S.,  R.  6  E. 
Jose  Mariano,  of  San  Simeon,  owner.  This  is  southeast  of  the 
North  Star. 

Vulture  Mine. — Oceanic  District.  In  Sec.  24,  T.  27  S.,  R.  9  E. 
F.  Eehman,  G.  E.  Van  Gordon,  and  E.  S.  Rigdon,  of  Cambria, 
San  Luis  Obispo  County;  A.  F.  Benton,  of  San  Miguel,  San 
Euis  Obispo  County;  and  G.  W.  Harris,  of  Pleyto,  Monterey 
County,  owners.  This  property  is  located  on  croppings  of 
black,  flinty,  siliceous  rock,  more  or  less  charged  with  cinna- 
bar, in  a  belt  of  serpentine.  Only  very  shallow  surface  work 
has  been  done,  so  that  nothing  which  determines  the  persistence 
in  depth  or  the  form  of  the  deposit  has  been  disclosed.     In  one 


168  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

open  cut  a  stratum  of  clay  from  2  to  3  feet  wide  is  exposed, 
which  on  panning  shows  to  carry  sensible  amounts  of  cinnabar. 

William  Tell  Mine,— Adelaide  District.  In  Sec.  32,  T.  26  S.,  R. 
10  E.  A.  J.  Brunoni,  of  Cambria,  owner.  This  lies  to  the  west 
of  the  Karl  mine,  on  the  same  ledge  of  croppings.  A  tunnel 
60  feet  long  has  been  run,  but  no  pay  ore  has  been  found  as  yet. 

Wittenberg  Mine. — Oceanic  District.  In  Sec.  8,  T.  27  S.,  R.  9  E. 
D.  F.  Wittenberg,  of  Cambria,  owner.  This  mine  lies  against 
a  wide  belt  of  "mudrock,"  but  judging  from  the  surface  indi- 
cations, is  underlaid  by  serpentine.  All  works  are  inaccessible 
at  present.     The  owner  is  at  work  reopening  them. 

SANTA  CLARA  COUNTY. 

The  New  Almaden  district  lies  southeast  of  San  Jose,  and 
covers  part  of  the  northeasterlj^  foothills  of  the  Gabilan  range, 
and  a  portion  of  the  Santa  Clara  Valle5^  [See  map  of  the 
New  Almaden  Mining  District.]  Through  the  latter  run  two 
spurs  of  low  hills  having  a  general  northwestern  direction, 
both  diminishing  in  elevation  in  this  direction  and  disappear- 
ing a  couple  of  miles  southeast  of  San  Jose,  where  the  valley 
covers  the  entire  territory  between  the  Gabilan  and  Mount 
Diablo  ranges.  One  of  these  spurs,  the  Santa  Teresa  hills, 
runs  between  the  Arroyo  Seco  and  Coyote  Creek,  and  the  other 
between  Coyote  and  Silver  creeks.  The  New  Almaden  and 
Guadalupe  mines  are  situated  on  a  ridge  which  forms  the 
southeastern  boundary  of  that  part  of  the  Santa  Clara  Valley 
having  a  general  direction  N.  45°  \\  .,  and  connected  at  one 
point  with  the  main  body  of  foothills  of  the  Gabilan  range. 
This  ridge  is  cut  through  at  the  southeast  by  the  Las  Animas 
cafion,  a  very  deep  incision,  in  which  are  located  the  hacienda 
and  furnaces  of  the  New  Almaden  mine.  It  deer-eases  gradu- 
ally in  elevation  going  to  the  northwest,  and  is  cut  ofi  north- 
west of  the  Guadalupe  mine  by  the  caiion  of  Capitancillos 
Creek. 

These  three  ridges  are  to  a  great  extent  formed  by  serpen- 
tine, especially  the  two  first  named.  The  serpentine  is  asso- 
ciated with  metamorphic  sandstone  and  j  aspilites.  Large  bodies 
of  croppings  can  be  found  in  each  of  these  ridges,  having  also 
a  general  northwestern  trend,  but  not  coinciding  with  the  back- 
bone of  the  ridges. 


tola'J/IoM  A' 


TDIMT. 


fEVERGREEN/ 


■'>■  '  7  f  •  <.  >.      ir. 


ILLSDALE 

STATION         :. 

Mo  EOENVALE 

^'^s-.^     STATION 


^.o^ 


Orat^n  by  CNararrtore. 


Green  =  Str[>enline,        Vellou  ^Melamorphk  Seri-s  BUit  =  Miocent 

MAP    OF    THK    NEW   ALMADEK   MINING   DIvSTRICT. 

Issued  l>y  the  Califoniia  State  Mining  Bureau  -  Lewis  E.  Aubury,  State  Mineralogist,    1903. 


SANTA  CLARA  COUNTY.  169 

In  the  New  Almaden  ridge  the  most  extensive  ore  bodies 
have  been  found  in  and  close  to  Mine  Hill,  the  highest  peak  of 
the  ridge,  lying  in  its  southeastern  part.  From  this  point  going 
northwestward  the  croppings,  while  not  continuous,  can  be 
traced  along  the  ridge  into  the  territorj^  of  the  Guadalupe  mine, 
a  distance  of  about  3)^  miles.  At  the  surface  the  serpentine 
shows  in  large  detached  bodies  surrounded  by  the  sandstones 
and  shales  of  the  Franciscan  series  and  having  a  general  north- 
western trend.  This  general  direction  of  the  serpentine 
exposures  is  important  in  connection  with  its  occurrence 
underground,  proven  in  the  New  Almaden  mine.  The  line  of 
ore  croppings  runs  from  Mine  Hill  to  the  America  shaft,  pass- 
ing about  600  feet  southwest  of  the  Randol  shaft.  The  under- 
ground workings  in  this  territory  have  shown  that  the  fissures 
wherein  the  ore  bodies  have  formed  have  invariably  a  serpen- 
tine foot  wall;  hence  the  serpentine  must  be  considered  to 
occur  underground  in  a  continuous  bod}^  through  this  entire 
territory  and  to  be  in  places  covered  by  overlying  sandstones 
and  shales.  Southwest  of  Capitancillos  Creek  lies  another 
parallel  exposure  of  serpentine,  contiguous  to  which  the  out- 
crops of  the  Costello  mines  are  found.  The  Santa  Teresa  and 
Bernal  mines  are  located  in  the  serpentine  of  the  Santa  Teresa 
hills,  and  the  North  Almaden  or  Silver  Creek  mine  close  to 
those  of  the  most  northern  ridge.  In  the  latter  a  great  part  of 
the  serpentine  is  very  highly  altered  by  silicification,  as  also 
the  sandstones,  a  great  portion  of  the  rocks  being  jaspilites. 
The  western  slope  of  the  adjoining  Mount  Diablo  range  is 
nearly  exclusively  formed  of  shales. 

In  this  district  the  occurrence  of  cinnabar-carr>4ng  ore 
bodies  is  clearly  closely  allied  to  that  of  serpentine,  and  as  the 
New  Almaden  was  the  first  extensively  worked  quicksilver 
mine  in  California,  this  association  explains  the  reason  why, 
for  a  considerable  lapse  of  time,  cinnabar  ores  were,  in  the 
opinion  of  most  quicksilver  miners,  considered  related  to  this 
rock  formation.  The  croppings  consist  of  a  more  or  less 
weathered  material  having  usualh'  an  ochreous  color  from  the 
oxidation  products  of  the  iron  sulphides,  and  traversed  by  a 
network  of  quartz  seams,  from  a  knife  blade  to  quarter  of  an 
inch  wide.  Overlying  the  ore  bodies  is  almost  invariably  found 
a  body  of  clay,  generally  black,  and  containing  more  or  less 
inclusions  of  a  dark-gray  sandstone.     As  this  clay  overlies  the 


•^> 


J  a 


*y^ 


..*=<^ 


.e^       W  < 


:>j 


>.ftr«\*>«.>A  ."S  ^^  tv•«x>•^t 


:c  ;:\M   -  \r-zH 


SANTA  CLARA  COUNTY.  169 

In  the  New  Almaden  ridge  the  most  extensive  ore  bodies 
have  been  found  in  and  close  to  Mine  Hill,  the  highest  peak  of 
the  ridge,  lying  in  its  southeastern  part.  From  this  point  going 
northwestward  the  croppings,  while  not  continuous,  can  be 
traced  along  the  ridge  into  the  territory'  of  the  Guadalupe  mine, 
a  distance  of  about  3^  miles.  At  the  surface  the  serpentine 
shows  in  large  detached  bodies  surrounded  by  the  sandstones 
and  shales  of  the  Franciscan  series  and  having  a  general  north- 
western trend.  This  general  direction  of  the  serpentine 
exposures  is  important  in  connection  with  its  occurrence 
underground,  proven  in  the  New  Almaden  mine.  The  line  of 
ore  croppings  runs  from  Mine  Hill  to  the  America  shaft,  pass- 
ing about  600  feet  southwest  of  the  Randol  shaft.  The  under- 
ground workings  in  this  territory  have  shown  that  the  fissures 
wherein  the  ore  bodies  have  formed  have  invariabl}'  a  serpen- 
tine foot  wall;  hence  the  serpentine  must  be  considered  to 
occur  underground  in  a  continuous  bodj-  through  this  entire 
territor\-  and  to  be  in  places  covered  by  overlying  sandstones 
and  shales.  Southwest  of  Capitancillos  Creek  lies  another 
parallel  exposure  of  serpentine,  contiguous  to  which  the  out- 
crops of  the  Costello  mines  are  found.  The  Santa  Teresa  and 
Bernal  mines  are  located  in  the  serpentine  of  the  Santa  Teresa 
hills,  and  the  North  Almaden  or  Silver  Creek  mine  close  to 
those  of  the  most  northern  ridge.  In  the  latter  a  great  part  of 
the  serpentine  is  xery  highly  altered  by  silicification,  as  also 
the  sandstones,  a  great  portion  of  the  rocks  being  jaspilites. 
The  western  slope  of  the  adjoining  Mount  Diablo  range  is 
nearly  exclusively  formed  of  shales. 

In  this  district  the  occurrence  of  cinnabar-carrj-ing  ore 
bodies  is  clearly  closely  allied  to  that  of  serpentine,  and  as  the 
New  Almaden  was  the  first  extensively  worked  quicksilver 
mine  in  California,  this  association  explains  the  reason  why, 
for  a  considerable  lapse  of  time,  cinnabar  ores  were,  in  the 
opinion  of  most  quicksilver  miners,  considered  related  to  this 
rock  formation.  The  croppings  consist  of  a  more  or  less 
weathered  material  having  usually  an  ochreous  color  from  the 
oxidation  products  of  the  iron  sulphides,  and  traversed  by  a 
network  of  quartz  seams,  from  a  knife  blade  to  quarter  of  an 
inch  wide.  Overlying  the  ore  bodies  is  almost  invariably  found 
a  body  of  clay,  generally  black,  and  containing  more  or  less 
inclusions  of  a  dark-gray  sandstone.     As  this  clay  overlies  the 


170  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

ore  bodies  it  has  received  the  name  of  "alta  "  (Spanish — "  over," 
"above").  At  the  surface  this  "alta"  crops  as  a  light-gray 
material,  resembling  disintegrated  sandstone,  traversed  by  a 
network  of  ver\-  thin,  yellowish-brown  seams,  often  very  much 
like  a  bunch  of  very  fine  roots.  In  places  the  same  material 
can  be  found  in  the  Xew  Almaden  mine  several  hundred  feet 
below  the  surface,  forming  part  of  the  "alta."     The  same  surface 


Shale  I     Croppin gs  ^jSerpentine 

~e/o  ~%  /20' 


Fig.  55.    Section  near  R.  R.  B.  shaft,  Xew  Almaden  property. 

cropping  of  "alta  "  can  be  seen  in  San  L,uis  Obispo  County.  [See 
general  description  of  Adelaide  district.] 

In  a  few  places  a  good  section  of  the  formation  has  been 
exposed  at  the  surface,  as  for  instance,  the  R.  R.  B.  shaft  of 
the  Enriquita  mine,  northwestern  part  of  the  Xew  Almaden 
mine,  and  near  the  Randol  shaft  of  same  mine.  [See  Figs.  55 
and  56.]     Both  these  sections  indicate  that  the  hanging  wall 

Serpentine\       4l_\^j^f\  il  v\— — 

FiG.  56.     Section  on  road  above  Randol  shaft,  Xew  Almaden  Mine. 

proper  may  be  a  shale,  which,  however,  is  so  decomposed  at 
the  surface  that  nothing  can  be  said  as  to  its  actual  character. 
About  300  feet  below  the  collar  of  the  R.  R.  B.  shaft,  in  the 
Eldridge  tunnel,  the  same  formation  can  be  seen  underground, 
that  is,  the  serpentine  foot  w^all,  the  vein  and  the  overhing 
"alta";  but  as  no  crosscut  has  been  driven  through  the  latter, 
no  further  information  as  to  the  character  of  the  hanging  wall 
proper  is  available.  The  clay  "alta"  is  but  an  attrition  prod- 
uct of  the  movement  of  the  walls  of  the  fissure,  and  hence  to 
call  the  "alta"  a  wall  of  the  vein,  as  is  frequenth'  done,  is 
a  misuse  of  geological  terms.  The  rocks  of  the  Franciscan 
series  in  this  region  show  a  great  amount  of  silicification.  The 
chert  beds  are,  however,  almost  entirely  unrepresented. 


SANTA    CLARA    COUNTY.  171 

To  the  west  of  the  New  Almaden  ridge  a  belt  of  bedded 
sandstone  is  exposed.  The  beds  are  from.  3  to  5  feet  thick  and 
interbedded  with  thinner  beds  of  shale.  The  sandstone  is 
rather  coarse,  and  has  been  classified  by  Dr.  Becker  as  Miocene. 
[See  Mon.  XIII,  U.  S.  G.  S.,  page  312.]  The  strike  is  about 
east  and  west,  dip  northerly,  not  over  20°.  The  country-  west 
of  the  New  Almaden  ridge  and  south  of  Capitancillos  Creek, 
belonging  to  the  Gabilan  mountain  system,  consists  almost 
exclusively  of  the  sandstones  and  shales  of  the  Franciscan 
series,  with  occasionally  some  jaspilites.  A  small  exposure  of 
serpentine  was  found  about  two  miles  west  of  the  New  Alma- 
den ridge,  close  to  the  main  ridge.  West  of  the  serpentine 
belt  which  lies  west  of  the  New  Almaden  ridge,  south  of  Cos- 
tello's  house,  a  small  exposure  of  glaucophane  schist  was 
found.  A  body  of  rhyolite  lies  in  the  northern  part  of  the 
New  Almaden  ridge,  having  a  nearly  east  and  west  strike  and 
being  about  two  miles  long.  To  the  east  smaller  bodies  of 
rhj'olite  are  found,  probably  the  continuation  of  the  same  bod}-, 
which  must  be  covered  up  in  the  inten'ening  space.  This 
eruptive  body  apparentlv  has  no  relation  with  the  ore  deposi- 
tion in  this  district. 

The  general  character  of  the  ore  tends  more  to  the  conclusion 
that  the  ore  deposition  was  a  feature  of  an  intense  silicification 
of  the  fractured  parts  of  the  serpentine;  that  the  fractured  zone 
was  a  favorable  channel  for  the  percolating  solutions,  which 
dissolved  the  ferro-magnesian  silicates  and  other  salts  of  the 
rock,  and  replaced  them  by  silica,  calcite,  dolomite  and  allied 
minerals,  sulphides  of  iron  and  occasionally  of  mercury ;  these 
channels  being  limited  on  one  side  by  the  impermeable  stratum 
of  clay,  the  "alta";  on  the  other  side,  by  the  limit  of  fracturing 
of  the  serpentine. 

There  are  some  small  areas  of  limestone  in  this  district.  The 
most  prominent  are  along  the  south  bank  of  Capitancillos 
Creek,  where  near  the  Guadalupe  mine  a  limekiln  was  in 
operation  at  one  time.  It  appears,  however,  that  the  product 
was  not  quite  satisfactory,  which  was  due  to  the  presence  of 
bitumen  in  the  rock. 

Bernal  Mine. — This  is  situated  on  the  east  slope  of  the  Santa 
Teresa  hills,  about  8  miles  southeast  of  San  Jose  and  near 
Edenvale  station,  on  the  Southern  Pacific  main  line.     Ygnacio 


172  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

Bernal,  No.  207  Balbach  street,  San  Jose,  owner.  This  prop- 
erty is  traversed  by  a  ravine  having  a  northeasterly  course, 
draining  into  Coyote  Creek;  on  both  sides  of  this  ravine,  but 
especially  on  the  northwest  side,  where  the  workings  are 
located,  are  found  some  ver^^  prominent  croppings.  The  lat- 
ter are  entirely  surrounded  by  serpentine,  but  as  far  as  ascer- 
tained do  not  connect  with  those  on  the  southeast  slope  of  the 
ravine.  The  direction  of  these  croppings  is  about  northwest. 
A  tunnel,  course  nearly  west,  about  215  feet  long,  is  run  on  the 
contact  of  the  "alta"  and  the  serpentine;  about  30  feet  from 
the  breast  a  good  exposure  of  the  formation  shows  the  vein  to 
dip  slightly  northeast,  with  a  clay  gouge  on  both  sides.  A 
short  crosscut  to  the  left  shows  that  the  overlying  gouge  is  at 
least  15  feet  wide.  The  gangue  is  of  a  ver>-  calcareous  nature. 
Nearly  200  feet  above  this  tunnel,  on  the  top  of  the  ridge,  a 
shaft  65  feet  deep  has  been  sunk  on  the  croppings,  showing 
some  good  ore  on  the  dump.  About  20  feet  southeast  of  this 
shaft  a  shallower  shaft,  not  over  20  feet  deep,  on  the  same 
croppings,  shows  a  more  ochreous  vein  material. 

Comstock  Mine. — This  lies  in  the  extreme  southeastern  corner 
of  Santa  Clara  Count}',  in  Sec.  19,  T.  11  S.,  R.  7  E.,  really 
belonging  to  the  Sta3-ton  Mining  District.  H.  French,  of  Lone 
Tree,  San  Benito  County,  owner.  [Report  State  Mining  Bureau 
of  Cal.,  XII,  page  367.]  The  property  is  at  present  abandoned. 
Some  old  surface  workings  and  remnants  of  an  old  furnace  can 
5-et  be  seen.  The  mine  is  located  on  the  only  surface  exposure 
of  serpentine  found  in  the  Stayton  Mining  District.  The  ore 
found  is  a  black  chalcedonic  quartz. 

Costello  Mine. — This  lies  on  the  southwest  side  of  Capitancillos 
Creek,  about  1^2  miles  southeast  of  the  Guadalupe  mine,  and 
opposite  the  Enriquita  mine  of  the  New  Almaden  propert}'. 
M.  Costello,  of  New  Almaden,  Santa  Clara  County,  owner. 
The  principal  workings  in  this  propert}'  are  located  on  the 
sidehill,  about  400  feet  above  the  level  of  Capitancillos  Creek; 
below  these,  considerable  limestone  is  found  in  the  debris 
covering  the  sidehill,  and  also  some  croppings  of  the  same  rock, 
but  at  the  level  of  the  works  this  rock  does  not  occur.  The 
works  consist  of  several  shallow  cuts  and  drifts  in  the  debris 
covering  the  hillside.  One  tunnel  reaches  through  the  latter 
into  the  serpentine.     In  a  crosscut  from  this  tunnel  a  sand- 


SANTA    CLARA    COUNTY.  173 

Stone  was  found  having  on  the  fracture  planes  a  thin  black 
coating  of  iron  and  carrying  some  cinnabar.  All  through  the 
debris  pieces  of  ore  are  disseminated,  composed  of  fragments  of 
a  flinty  material,  generally  in  a  matrix  of  quartz;  occasionally 
the  matrix  resembles  the  tuffoid  of  the  Abbott  mine.  Lake 
County.  The  character  of  the  ore  is  entirely  different  from 
that  in  the  New  Almaden  ore  bodies.  No  ore  deposits  in  place 
have  yet  been  found. 

Guadalupe  Mine. — This  mine  is  on  Capitancillos  Creek,  lo 
miles  south  of  San  Jose.  The  Century  Mining  Company, 
owner;  H.  C.  Davey,  president,  F.  A.  Lueddeman,  secretar}^ 
San  Jose,  Santa  Clara  County;  San  Francisco  office,  room  131 2, 
Claus  Spreckels  Building.  [See  Report  State  Mining  Bureau 
of  Cal.,  Vm,  page  542;  XIII,  page  600;  Mon.  XIII,  U.  S.  G.  S., 
page  326.]  This  mine  was  discovered  in  the  early  50's,  being 
acquired  soon  after  its  discovery  by  the  Santa  Clara  Mining 
Association  of  Baltimore,  Md.,  and  was  operated  by  that  com- 
pany until  the  mine  was  bought  by  the  Guadalupe  Mining 
Company  of  California  in  1875,  when  large  surface  improve- 
ments in  the  way  of  reduction  works  and  mining  machinery 
were  installed  and  extensive  mine  development  work  was 
prosecuted.  Up  to  1886  the  mine  produced  55,910  flasks  of 
quicksilver  [see  Mon.  XIII,  U.  S.  G.  S.,  page  11],  and  then 
remained  idle  until  1900,  when  H.  C.  Davey  organized  the 
Century  Mining  Company-,  which  has  remodeled  the  reduction 
plant,  started  to  unwater  the  mine,  and  is  at  present  passing 
through  the  furnace  a  great  part  of  the  old  dumps  and  some 
fillings  of  the  upper  parts  of  the  old  works.  The  unwatering 
of  the  mine  has  proven  a  very  difiicult  undertaking,  as  the 
works  are  at  a  shallow  depth  under  Capitancillos  Creek,  which 
drains  a  large  section  of  the  country. 

From  the  plan  of  the  old  works  it  can  be  seen  that  the  ore 
body  developed  b}'  the  main  vertical  shaft,  located  on  the 
south  side  of  the  creek,  had  a  northwest  strike  and  southwest 
dip.  The  second  level,  300  feet  below  the  collar  of  the  shaft, 
connects  with  an  incline  shaft  started  on  the  opposite  bank 
of  the  creek  and  following  the  vein  on  its  dip.  The  main 
shaft  was  only  sunk  to  the  sixth  level  (625  feet).  From  this 
level  an  incline  shaft  was  sunk,  from  which  the  seventh, 
eighth,  and  ninth  levels  were  driven.     Ore  was  only  developed 


174  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

in  the  seventh  and  eighth  levels.  Besides  these  works  several 
other  shallower  shafts  and  drifts  were  run,  all  practically  inac- 
cessible. 

The  property  is  equipped  with  two  20-ton  coarse-ore  fur- 
naces and  two  40-ton  fine-ore  furnaces,  modeled  according  to 
the  Davey  patent. 

Hillsdale  Mine,  or  old  Chapman  mine,  formerly  known  as  the 
Chaboya  mine,  about  two  miles  from  San  Jose,  near  Hillsdale 
station,  lies  on  the  east  slope  of  the  northwestern  end  of  the 
Santa  Teresa  hills.  Oscar  Promis,  No.  246  South  Third 
street,  San  Jose,  owner.  There  are  a  great  number  of  excava- 
tions in  the  hillside,  which,  however,  reach  scarceh'  any  depth, 
as  the  crest  of  the  hill  is  not  over  100  feet  above  the  level  of 
the  valley.  At  present  these  workings  show  ver^^  little  ore. 
They  must  at  one  time  have  produced  quicksilver  ore,  as  the 
remnants  of  an  old  furnace  are  still  on  the  premises. 

New  Almaden  Mine. — This  property  lies  1 3  miles  south  of  San 
Jose,  and  covers  a  territory  of  8580  acres.  The  Quicksilver 
Mining  Company,  owner;  A.  I^.  Baile}^  20  Nassau  street,  New 
York,  president;  Thomas  Derby,  New  Almaden,  Santa  Clara 
Count}^  superintendent.  [See  Mon.  XIII,  U.  S.  G.  S.,  page  310 
and  following;  Report  State  Mining  Bureau  of  Cal.,  VIII,  page 
541;  X,  page  604;  XII,  page  370;  XIII,  page  600.] 

This  property  is  the  oldest  known  quicksilver  mine  in  the 
United  States.  It  was  first  worked  in  1824  b}^  Antonio  Sunol, 
lyuis  Chaboya,  and  Robles,  and  was  known  as  the  Chaboya 
mine.  In  1845,  Andreas  Castillero,  a  Mexican  army  officer, 
"denounced"  the  mine  under  the  name  of  Santa  Clara  mine. 
After  the  admission  of  California  into  the  United  States,  Castil- 
lero and  his  associates  leased  the  mine  for  sixteen  years  to  the 
banking  firm  of  Barron,  Forbes  &  Co.  The  name  of  the  mine 
was  at  the  same  time  changed  to  that  of  New  Almaden.  Ir 
1864  the  property  came  into  the  hands  of  the  present  owner. 

This  mine  produced  in  the  earlier  years  comparativelj-  rich 
ore,  but  in  later  years  the  richness  of  the  ore  has  very  much 
decreased  and  that  now  worked  is  of  about  the  general  average 
grade  of  that  in  the  other  large  quicksilver  mines  of  the  State. 
The  table  on  pages  176  and  177  gives  its  production  up  to  the 
year  1896. 


Bueno  yisfa  Shaft 


/fandol  Tunnel 


Sec f  ion    A  A 


^      MoinShaft'    J  \         i,         '-^, 


A 


'.  fforr/  S/!aft 


Washingfon       %1 
Shaff      •<' 


^S> 


ffatf  Turfte/ 


SCALCIN  nCT 


I         .  I  Ore  bodies  y/ren  /n  Map  of  Or.  Beefier  ftSS. 
\'         I  Ore  bocfies   cfefe/ofiecf  /afer 


Ore  Uoilies  in  the  New  Almaden  Mijic. 


SANTA  CLARA  COUNTY, 


175 


The  mine  workings  cover  a  ter- 
ritory of  about  2'^  square  miles,  ex- 
clusive of  those  in  the  northwestern 
part  of  the  property.  The  greatest 
depth  of  these  workings  is  2450  feet 
below  the  top  of  Mine  Hill,  which  is 
used  as  the  datum  point  for  all  under- 
ground workings.  In  this  territor)^ 
eighteen  shafts  have  been  sunk,  and 
the  underground  excavations  would 
be  about  84  miles  long.  The  greater 
part  of  these  extensive  workings  are 
at  present  inaccessible;  the  Mctoria 
shaft,  a  short  distance  to  the  south- 
west of  the  Randol  shaft,  and  the 
Harr}'  shaft,  on  the  southeast  slope 
of  Mine  Hill  [see  map,  Fig.  57],  are 
the  only  two  shafts  at  present  in 
operation.  The  deepest  workings  at 
present  followed  are  1000  feet  below 
the  datum  point;  and  below  1300  feet 
the  mine  is  filled  with  water. 

The  ground  in  that  part  of  the 
mine  now  in  operation  is  remarkably 
good.  A  majorit}'  of  the  large  stopes 
are  held  up  with  scarcely  any  timber- 
ing, and  onl}^  in  some  parts  of  the 
mine  is  square-set  timbering  required. 
Most  of  the  gangways  require  only 
occasional  timbering  for  short  dis- 
tances. The  ground  in  the  Randol 
shaft  formerly  worked  was,  however, 
much  heavier. 

The  gangways  are  driven  on  the 
contact  of  the  clay  gouge,  locall}- 
called  "alta,"  which  overlies  the  ore 
bodies,  and  where  the  ore  bodies  are 
absent,  on  the  contact  of  the  "alta" 
with  the  serpentine  foot  wall,  locally 
called  "greenstone." 

The  ore  forms  principally  in  "stock- 
wercks"    (that   is,  in  large  zones    of 


176 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


z 

< 

> 

id 
o 

3 
c 

b 
O 

O 

P 
u 

Q 
O 

Oi 

a. 


•smnoK 


WMtNMCSMNM'^ 


CS(Nt^NC<l(NONP)<NM(SNMN 


JO  ppi.\ 


•SUSBXd 

jnnoinv  33. .vy 


^ 


wp-iC^MMMMN 


MrOC<NMrorOMMfN    —    "■    —    '- 


'S31SE1H 


to  I-"  lO  «0  O  rO  N  1^00 
r^  (N  rO  M  VO  00  O  •^OO 
CO   On  O   fOX    O   O   f^  "0 


low  '*0  r^ON-*0   "lOOCO   fOX   "*  M 
t^rOiOUO-^Tj-"   ►-   '*vO  X   ■*  lO  lO  O 


■sSaiqSBAV 
ino  JJ  's:^SBt.i 


<^  OnX  O   t^  fOvO  ■"*■->- 
voM'roO'-'"Nt^>o 

eT  i-T  n" 


•saDEnjnji 

lUOJJ  S3[SEU 


\n  >-i  lo  lo  o  f^  PI  t^x 

t-»P»    rOPIvOX    O    ■^X 
X   ON  O    rOX    O    O   rO  lO 


N  NvO  O  OvDX>0  O  t^X  <-0  ro  >-  N 
O^  '-  M  -^r^t^N  ONr^ONM^£>  ON'^ 
•^  M    rOX    O    —    O    t^  On  lOX    Tt  U-)  rO  O 


5 - 

Jo  3 

•H    O 


r^OOOOOOOiO 
'-'  ON  N  o  o  o  o  t^x 
t^M   lOO    rON    ON"    O 


OOOOOOOOfOOiOOOOiO 
OOvOOOOOOfOror^OOOt^ 


C   rO  OnX    on  lO  On  r^  fO 
OnvO  X    ■*  '-I    rO  M    OnX 


rO  "-    M  »£)    On  r^X    lO  (-0  lO  X    t^-^vD    O 

(NX  r-»'^u^t^-*x  N  c  ico^f^—  <^ 

rO  M    "    ro  r<^  PJ    ONX    O    •*  ■*  C    C    -^  fO 


•^•^^r^ONO    O    O    rO 


< 

Oi 

a 

S5 


2-S 

.2 

w     W     w     O    ^^  v^     L^     ul     w     ^     W 

OONiOtN^-t^OXOvCO 
X"  rC  O"  O"  rO  ■^^'  lO  rO  t-^X* 

"X  ^  -^  O  O  ^  for^ONfO 

r^  M    On  '*>0    ir>  i-O  lO  rO  'TX 
f^  ro  lO  OJ  eT  rOX'x'x'x' 

f  Graii/.a, 
Pounds. 

5 
>-( 

>N 

OOOOXOiOOOOiO 
OOOOXOr^OOOr^ 
lOfOO    —    M^    —    ONI^Oro 

vc"  c"  On  ON  C^^"  m'  — "  — "  t^  pi 
X    "^  -*  fOX  \£>    -J-  f^^    t^  ON 
u^  r^  r^  OnnD  in  CT<  iCvC   r^  ■* 

"X  inONir;-*-  M  ro<sx 

u  ? 

CO 

V 
tn 

O 

0 

oooooxoo 
oooooooo 

X_  -^  ON  0_  lO  tN    o_  o 

'T  (Sx\D    ~    TT  O'  O' 

in  lOX    C    r^  r^  m  ro 

M    pg    in  t^  PI    — 

pT 

M    PI    fO  "*  invO    t-»X  X    -I    PI    rO  f^  fO  f<l  ■*  mvO    I~~X    On  O    —    PI    rC 

ioioioininmminmo^vDv£>vO\OvD^DvCvCvovc  t^r^t^r^ 
xxxxxxxxxxxxxxxxxxxxxxxxx 


DOCJUilOOO 


„•  _•  „•  ic_;  y  -J 

~  ^  C  s  y  0)  ;/ 

1—1' — ii— i"^  ^  ^-  -^ 


1/    5J    y    il    y 


K    i>    01 


O  O  o  o  o  o 


ooooooococo 


o  ►-  pt  ro  ■^  invo  i^x  X  "  PI  fn  f^  r^  Tj-  mvc  r-^x  on  3  —  pi  fO 
lOinininininininin  in'O  vd^vOvooo^nOnOvo  f^t^r^r^ 

XqoXXXXXXXXXXXXXXXXXXXXXXX 


SANTA    CLARA   COUNTY. 


177 


OMtNtNNMCIOttNNP) 

M    CS    tN    N 

PI    p»   p«   P<  vO    P<   P< 

PI 
liO 

M    rO'^'^'^M   f<    er>  ^    M   >-• 

p<    11    CN    M 

►I    PI    1-1    O    i-"    M    O 

H,l_h-h->-iH-C<MtN>-i 

►H      M      «      1-1 

"    " 

Tj-00    CT^vO   N   -^  ID  O   O    O    O 
O  vO    "O  CT^X   »0  Tl-  O    O   O    O 

o  o  o  o 
o  o  o  o 
■^  o  o  o 

8882588 

1-1    0    P<  vO   'T  O    «0 

pT 

ON 

-  X    O  X 
M    ►-    M    — 

<-o  PI  X  lo  ON  r^vo 

x" 

t^  i-i   C^^O  <M  Tj-  lO  o   o   o    o 
\o  -rf  ^  (j\in  "^\D  r^O  O 
CO   lO  lO  CT<00   lO  "^  o    o    o   o 

8888 

8882588 

►-    O   P<  \0   Tl-  O    fO 

fO 

CO 
CO 

ON 

"  X   O  X 
CS    «    M    M 

rO  P<  X   >0  On  r^vO 

OOOOiOiOOiOOOOOOQOOOOOOOO 
00>OOMroiOrOOOOOCT\000000000 
OP^O^^OC^>-cOOl-'Mu^O   rc\£)   co^    CN  CO    t^  t^  CN    0\  r^ 

O 
Pt 

o     i 
"2 

ro  «  po  r^vo  lo—  -^M  r^oON^  -^r^-r^iO"  O^oo  <n  u-> 
N   <^>  PO  rO  t^  iO\0  vO   r^  C^  t^  t^OO  vO    lO  UO  •*  lO  lO  lO  lOvO 

QOCO'-OOiOOOO 
Q000t--u:>0r<000 
O    P<   -*vO    O    C    e*  vO   fO  O    O 

o"  0*  cT  r^  O*  fO  r^  cT  pT  u?  — " 
vO    I^  fO  Tt  CO  rOX    1-1    ►-.    ro  -^ 

UOX    rO  lO  t^  O    •^X    «    ON  PI 
M   UOOX   t--(NvO   Ovi-it^i-i 
T^p)  u-5—  fO(N  r^-*-*  ONX 

CO 
in 

ON 

CO 

PI 

t-^ 

CO 

P<  X  X   fO  e*   0^vO    CT^<N   lOiN    —   t^  —  \CX   r^ioio—    '-vC 

CO 

O 

PI 
PI 

CO 

M    C4    ^  rO  •^vO    lO  ^  0^  d  vO 

r^  -Tf  pt  " 

O^X   lO  fONO    O  X 

X 

& 

NO 

CO 

x" 

'^tovo  r^x  c^  o  •-'  N  "-o  ■* 

r^t^r^t^r^i^XXXXX 

xxxxxxxxxxx 

u-;^   r^X 
X  X  X  X 
X  X  X  X 

ON    O      ►-      PI      Tl-    lOvO 
X      ON   Ov    ON   ON   ON    ON 

X  X  X  X  X  X  X 

■s 

y  y  o  o  y  o  o  o  cj  o  u 

o  o  y  o 
y  o  o  o 

o  y  o  'J  ^  ^  ^ 

o  o  o  o  c  cl.  :i. 

c;  ~  C5  c;  <:  << 

coooooocooo 

0  O  0  o 

O    0    2    O    O   O    O 

o 

u 

O 

Tt  iCvO    t^X   On  O   "   N    O  Tj-  lO^O   t^X    On  3    —   <N    fO  •^  lO 
r^  r~  (^  r^  t--  t^X  XXXXXXXXX    Onc^O^OO^Ov 

XXXXXXXXXXXXXXXXXXXXXX 

CC    =    SS    =    I=    =    =    =    = 

n  =  =  = 

=    =    =    =    =    K  ^ 

^1— >■—>■— 1 

■^'^►^►^►^'^  ^ 

o      ? 
*       ii 


ON      - 

PI*     s 

5  5 

y  ^ 

•r.  ^' 


\M 


^ 

-l 

il 

t_^ 

^ 

■X 

y 

^ 

11 

X 

^ 

CO   Si 

On  -S 
.  O 
a;     1- 


'3-:2 


-    > 
5  ^ 


178 


QUICKSILVER    RESOURCES   OP   CALIFORNIA. 


fracturing),  and  in  reading  the  following  description  it  must 
be  borne  in  mind  that  when  speaking  of  veins  in  the  New 
Almaden  mine,  this  term  does  not  indicate  a  well-defined 
fissure,  but  that  the  ore  deposition  has  taken  place  along  zones 
of  fracturing.  Judging  from  the  great  width  of  the  "alta," 
the  result  of  attrition  caused  b}'  the  movements  of  the  rock 

niNE  HILL 


Fig.  58.     Section  of  Mine  Hill,  New  Almaden. 

Strata,  from  the  wave-like  form  of  ore  deposits,  from  the  fact 
that  parallel  zones  of  ore  deposition  are  found,  and  finally  from 
the  character  of  the  vein  filling,  which  shows  repeated  fissuring 
and  refilling,  resulting  in  a  ribbon  formation  in  the  seams,  the 
conclusion  must  be  drawn  that  this  fracturing  was  persistent 
during  a  long  period  of  time. 

The  ore   deposits   are   limited   on   their   hanging-wall  side 

by  the  "alta,"  an 
'Gi'onfpZv^^^  impermeable  stra- 
tum through  which 
no  water  circula- 
tion could  pass. 
The  foot-wall  side 
is  persistently  ser- 
pentine, hence  it 
must  be  concluded 
that  in  this  mine 
the  serpentine  is  associated  with  the  cause  of  fracturing  of  the 
other  rock  strata,  and  this  would  lead  to  the  conclusion  that 
here  the  serpentine  must  be  considered  as  an  alteration  prod- 
uct of  intrusive  peridotites,  not  as  an  alteration  of  strata  of 
the  Franciscan  series.  This  conclusion  finds  confirmation  by 
a  section  of  the  country  from  Mine  Hill  toward  the  Washing- 
ton shaft.      [See  Fig.  58.]     The  fracturing  has  taken  place  on 


Fig. 


59.     Section  over  Santa  Rita  West,  Giant  Powder 
slopes,  New  Almaden. 


SANTA  CLARA  COUNTY. 


179 


both  sides  of  the  serpentine,  which  apparently  can  not  be  con- 
sidered otherwise  than  as  an  intrusive  body  having  uplifted  the 
rocks  of  the  Franciscan  series. 

The  ore  bodies  form  principallj^  in  those  parts  of  the  zones 
where  the  dip  of  the  "  alta  "  is  very  flat,  as  indicated  in  Fig.  59 — 
an  ideal  section  over  two  connected  stopes,  which  have  both 
produced   considerable  amounts   of  ore.     The  contact  of  the 


PHOTO  No.  16.     DL'.MP  OF  NEW  ALMADEN  MINE  WORKS. 

"  alta"  with  the  underlying  vein  filling,  and  where  this  is  miss- 
ing with  the  serpentine,  is  very  tortuous  in  both  directions, 
vertically  and  horizontally,  so  that  in  the  gangways,  which, 
as  above  mentioned,  follow  this  contact,  it  is  an  exception  to 
find  a  straight  line  of  any  length.  The  stopes  are  locally 
called  "labores."  The  material  which  fills  the  zones  of  frac- 
turing and  wherein  in  places  cinnabar  forms,  is  generally 
rather  hard  and  siliceous,  traversed  by  a  network  of  seams 

12— QR 


180 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


of  quartz  and  dolomite,  showing  repeated  Assuring  and  filling 
containing  some  inclusions  of  serpentine,  the  cinnabar  forming 
principally  in  connection  with  the  seams.  In  places  the  vein 
filling  has  more  of  an  ochreous  character,  the  matrix  being 
more  or  less  leached  out,  leaving  only  the  network  of  seams 
intact. 

The  San  Francisco  vein  is  mainly  composed  of  this  ochreous 


PHOTO  Xo.  17.    DUMP  OF  GREY  SHAFT  AND  MINE   HILL, 
XEW  ALMADEN. 

ore,  wherein  are  found  bodies  of  ven,-  hard  rock,  resembling 
diorite,  verj'  irregularly  fractured.  In  this  vein,  the  ochreous 
material  lies  on  the  serpentine,  no  gradual  change  taking  place 
from  the  former  into  the  latter,  which  for  from  8  to  lo  feet  from 
the  vein  is  changed  into  a  clayey  material,  gradually  changing 
into  hard  serpentine. 

The  general  character  of  the  vein  filling  indicates  that,  as  in 
most  of  the  other  quicksilver  deposits  in  the  State,  the  deposi- 


SANTA    CLARA    COUNTY. 


181 


tion  of  cinnabar  has  been  associated  with  the  process  of  silici- 
fication,  which  characterizes  the  alteration  of  the  rocks  of  the 
Franciscan  series. 

The  general  direction  of  the  seams  in  the  vein  filling  is  not 
parallel  to  the  line  of  contact  with  the  "alta."  The  "alta" 
is  often  indurated  near  the  vein,  and  is  then  locally  called 
"cab."     This  is  especialh'  the  case  in  the  upper  workings.     In 


PHOTO  No.  is.     VICTOKl.\  SHAFT,  NEW  ALM.\DEN. 

the  lower  levels,  it  has  more  the  character  of  a  moist  clay ;  the 
inclusions  of  gray  sandstone,  so  frequent  in  the  mines  of  San 
Luis  Obispo  and  San  Benito  counties,  while  not  absent,  are 
much  less  prominent.  Possibly  associated  with  this  change  in 
the  character  of  the  "alta"  is  a  difference  in  the  distribution 
of  the  cinnabar  in  the  pay  shoots.  In  the  upper  workings  the 
part  nearest  to  the  "alta"  is  seldom  the  richest,  the  cinnabar 
forming  more  plentiful  at  from  5  to  8  feet  below  the  "alta," 


182 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


while  in  the  lower  workings  the  richest  ore  is  invariably  close 
to  the  "alta." 

The  contact  between  the  "alta"  and  the  vein  filling  is  very 
sharplj'  marked,  but  there  is  a  gradual  change  of  the  above 
described  vein  filling  into  the  material  of  the  serpentine  foot 
wall,  the  vein  material  gradually  carrying  more  serpentine, 
until  its  has  entirely  changed  into  the  latter.     The  hanging 


PHOTO  No.  19.     SANTA  ISABEL  SHAFT,  NEW  ALMADEN 

wall  is  a  shale,  judging  from  surface  exposures.  Underground, 
no  crosscut  through  the  "alta"  to  the  hanging  wall  was  seen. 
[See  Figs.  55  and  56.] 

In  some  parts  of  the  mine,  especially  in  the  lower  workings 
(as/,  i),  in  the  drift  from  the  Santa  Isabel  shaft,  southwest  to 
the  American  shaft  [see  plan,  Fig.  57],  heavy  flows  of  gas  were 
encountered,  principall}^  if  not  exclusively,  consisting  of  car- 
bon dioxide,  which  in  that  drift  were  so  strong  as  to  force  the 


SANTA    CLARA    COUNTY. 


183 


company  to  abandon  the  work.  It  is  generally  supposed  that 
this  gas  is  generated  by  the  decomposition  of  the  calcite  and 
dolomite,  which  are  abundant  in  those  parts  of  the  mine,  both 
in  the  vein  filling  and  in  the  "  alta." 

In  order  to  give  an  intelligible  description  of  the  formation 
of  the  ore  bodies  in  the  New  Almaden  mine,  the  old  works,  at 
present  inaccessible,  must  be  taken  into  account.     The  magnifi- 


PHOTO  No.  20.     RANDOL  SHAFT,  NEW  ALMADEN. 

cent  map  of  the  underground  works  in  the  office  of  the  com- 
pany gives  ample  opportunity  to  do  this.  A  reduced  copy  of 
this  map,  up  to  the  date  of  its  publication,  1887,  is  found  in 
sheet  IX  of  the  atlas  of  Mon.  XIII,  U.  S.  G.  S.  The  accom- 
panying plan  [Fig.  57]  gives  an  outline  of  the  ore  bodies 
opened  up  in  the  mine.  The  later  works  are  located  princi- 
pally in  the  upper  levels. 

One  nearly  continuous  series  of  ore  bodies  {a)  lies  on  a  line 


184  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

Starting  near  the  main  shaft  and  going  in  a  northwesterly 
direction  to  about  400  feet  northwest  of  the  Santa  Rita  shaft, 
a  distance  of  about  one  fourth  of  a  mile.  These  ore  bodies  are 
worked  to  a  depth  of  not  over  700  feet  below  datum  level  (top 
of  Mine  Hill).  In  the  southern  part,  near  the  main  shaft,  the 
ore  bodies  are  intricately  overlying  each  other.  [See  Fig.  57, 
crosscut  AA,  a  west-east  section  over  this  part  of  the  mine.] 
This  may  be  due  to  the  intrusive  serpentine  body  in  Mine  Hill 
before  mentioned. 

A  second  series  of  ore  bodies  {b)  lies  to  the  east,  and  runs 
nearly  parallel  to  the  former.  It  begins  a  little  southwest  of 
the  Harr3'  shaft,  and  runs  to  about  the  Day  tunnel,  where 
it  connects,  by  a  series  of  stopes  about  400  feet  long,  with 
the  first  mentioned  series.  These  workings  go  from  400  feet 
below  datum  in  their  southeastern  part  to  650  feet  at  the 
northwestern  end. 

Running  a  line  from  the  Giant  Powder  stope  to  the  Santa 
Maria  shaft,  the  general  direction  of  the  veins  south  of  this 
line,  judging  from  that  of  the  gangwaj^s,  which  as  stated 
above  are  run  along  their  hanging  contact,  is  about  north 
with  an  east  dip.  North  of  this  line  the  ore  bodies  appear  to 
change  their  course  and  to  lie  on  a  nearly  southwest  strike 
with  a  northwest  dip.  In  this  latter  part  of  the  mine  there 
are  two  distinct  zones  of  mineralization — the  western  zone 
{c),  which  connects  directly  with  the  first  above-mentioned 
series,  and  the  eastern  zone  {</),  which  appears  to  be  separated 
from  the  second  series  {b)  by  a  nearly  barren  zone,  in  which, 
however,  not  only  does  the  vein  persist,  but  the  two  zones 
mentioned  by  Dr.  Becker  (Mon.  XIII,  U.  S.  G.  S.,  page  320 
et  seq. )  make  their  appearance,  there  being  two  levels  run 
on  the  900-foot  and  looo-foot  levels  on  their  hanging-wall 
contact.  From  the  700  to  the  1 700-foot  level,  there  is  a  barren 
zone  between  these  two  mineralized  zones  {c  and  d).  On 
the  latter  level  a  body  of  ore  was  worked  between  them, 
but  judging  from  the  map  of  the  underground  workings  of  the 
company,  *below  this  level,  no  ore  bodies  were  found  in  the 
intervening  space.  [See  plan.  Figs.  57  and  60,  which  give  a 
general  idea  of  this  system  of  ore  deposit.] 

In  the  1400-foot  level,  Santa  Isabel  South,  running  toward 
the  Washington    shaft,   about    700  feet   south  of   the  Santa 


dol  Shaft 
jT  Col/<"' 


SCAL£  W  r££T 

O      so     /OO         200  300 


Fig.  60. 

Plan  of  the  Clay  Walls,  New  Almaden  Mine. 
From  Atlas,  Monograph  XIII,  V.  S.  G.  S. 


SANTA    CLARA    COUNTY.  185 

Isabel  shaft,  and  near  the  breast  of  the  1400-foot  level  south- 
west running  from  the  same  shaft  toward  the  America  shaft, 
some  ore  was  found.  If  these  ore  bodies  could  be  proven  to 
be  connected,  they  would  be  found  to  lie  in  the  prolongation 
of  the  strike  of  c  and  d,  and  there  would  appear  to  be  a  line  of 
cross-fissuring,  a  very  possible  occurrence  in  a  country  as 
disturbed  as  the  vicinity  of  the  New  Almaden  mine. 

In  the  knoll  southeast  of  Mine  Hill  are  the  Cora  Blanca 
workings,  which  in  former  times  yielded  quite  good  ore.  At 
present  a  tunnel  is  run  between  the  Cora  Blanca  and  Grey 
shafts  in  this  hill,  which  has  cut  a  small  ore  body;  the  latter 
has,  however,  an  entirely  different  appearance  from  that  in  the 
other  workings,  the  gangue  consisting  of  fragments  of  jaspery 
material  recemented  by  silica,  calcite,  and  dolomite.  The  cin- 
nabar is  here  associated  with  some  iron  pyrite. 

The  most  northwestern  works  on  the  property,  known  as  the 
Enriquita  mine,  are  located  about  i  %  miles  northwest  of  Mine 

Fig.  61.     Section  in  Enriquita  Mine,  New  Almaden. 

Hill.  The  lowest  working  is  a  tunnel  starting  on  a  very  promi- 
nent body  of  croppings,  which  in  the  tunnel  forms  a  sandstone 
traversed  by  a  very  close  network  of  seams  refilled  by  quartz 
and  calcite.  At  840  feet  from  the  entrance  the  tunnel  enters 
the  serpentine  and  splits.  The  left-hand  drift  runs  to  the 
bottom  of  the  R.  R.  B.  shaft,  and  then  follows  the  contact  of 
"alta"  and  vein  material,  which  at  the  breast  disappears, 
leaving  the  "alta"  directly  overlying  the  serpentine.  The 
right-hand  drift  also  reaches  a  similar  contact  and  stops  at  the 
contact  of  the  "alta"  and  the  serpentine,  showing  that  there 
is  here  also  a  repetition  of  strata.  [See  Fig.  61.]  Above  this 
level,  about  150  feet  below  the  surface,  a  body  of  very  good 
ore  was  worked  in  former  years,  from  which  about  10,000 
flasks  were  obtained. 

The  mine  is  equipped  with  two  coarse-ore  furnaces  of  12 
tons  capacity  each;  two  medium-sized  ore  (granitza)  furnaces, 
one  of  36  tons,  the  other  of  18  tons  capacity;  and  two  fine-ore 
(tierra)  furnaces,  one  of  36  tons,  the  other  of  24  tons  capacity. 

There  is  very  little  or  no  mining  timber   available  in    the 


186  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

vicinity.  The  company  uses  exclusively  Oregon  pine,  costing 
$i8  per  I  coo  feet  (B.  M.).  Cordwood  is  not  very  abundant, 
and  costs  $5. 85  per  cord.  The  company  uses  oil  as  fuel  under 
the  steam  boilers  in  both  hoists. 

Santa  Teresa  Mine* — This  is  situated  on  the  east  slope  of  the 
Santa  Teresa  hills,  about  8  miles  southeast  of  San  Jose,  near 
Edenvale  station,  on  the  Southern  Pacific  main  line.  The 
Santa  Teresa  Quicksilver  Mining  Company,  owner;  R.  B.  Har- 
per, of  San  Jose,  superintendent.  Three  tunnels  have  been  run 
in  the  mountain.      [See  Fig.  62.]     The  lowest  tunnel,  700  feet 


^Mt'f,         Surface 


Tunr)  el 


^e/n 


'£___^'      Top  of  Ridge  (835) 


Fig.  62.     Sketch  of  works  in  the  Sauta  Teresa  Mine.     Scale,  i":=2oo'. 

long,  reached  the  vein  at  550  feet  from  the  mouth;  its  course 
is  nearly  south.  It  turns  to  the  left  on  the  vein  and  is  driven 
in  toward  the  territory  under  the  two  upper  tunnels  in  order 
to  reach  the  pay  shoot  in  the  vein,  which  apparently  dips  east- 
ward. The  middle  tunnel,  no  feet  above  the  former,  course 
S.  8°  \V.,  325  feet  long,  is  in  serpentine.  It  cuts  the  ledge  228 
feet  from  the  mouth.  There  is  no  selvage  or  gouge  between 
the  ledge  and  the  serpentine.  The  ledge  stands  nearly  vertical; 
the  tunnel  has  not  yet  passed  through  the  ledge  into  the  oppo- 
site wall.  The  upper  tunnel  is  85  feet  above  the  middle  tunnel, 
course  S.  22^  W.  It  cuts  the  contact  of  the  serpentine  and  the 
ledge  at  220  feet  from  the  mouth,  and  a  few  feet  farther  turns 
to  the  right  in  the  ledge  and  runs  187  feet  in  this  direction. 


SANTA   CLARA   COUNTY.  187 

About  50  feet  from  its  turning  point  is  a  vertical  shaft,  which 
connects  with  the  middle  tunnel  about  90  feet  from  the  point 
where  the  latter  cuts  into  the  ledge,  showing  that  the  ledge 
dips  north.  Between  these  two  tunnels,  farther  on,  a  raise  goes 
from  the  upper  level  to  the  surface  no  feet,  all  in  ledge  matter. 
On  the  level  of  the  upper  turtnel  several  drifts  and  crosscuts 
have  been  run  in  the  ledge  matter,  showing  the  latter  to  be 
ver}^  extensive. 

The  country  rock  is  all  serpentine.  The  ledge  matter  varies 
greatly  in  character.  It  is  apparently  an  alteration  product  of 
serpentine  through  silicification,  subsequent  to  a  fracturing  of 
the  material.  The  fissures  have  been  filled  by  quartz  and  cal- 
cite,  the  silicification  varj'ing  in  difierent  zones  of  the  ledge, 
probably  due  to  a  varying  degree  of  fracturing.  In  places 
inclusions  of  nearly  unaltered  serpentine  are  found.  In  others, 
as  for  instance,  in  an  intermediate  short  level  run  from  the  shaft 
37  feet  above  the  middle  tunnel,  the  rocks  contain  a  great 
amount  of  cavities.  Considerable  ochreous  material  is  found, 
probably  due  to  the  oxidation  of  iron  pyrite.  A  50-ton  Scott 
furnace  is  in  course  of  construction. 

Silver  Creek  Mines. — This  was  formerly  the  North  Almaden 
mine,  on  the  east  side  of  Silver  Creek,  near  Evergreen,  about 
8  miles  from  San  Jose.  Silver  Creek  Quicksilver  Mining  Com- 
pan}',  owner;  H.  R.  Bradford,  president.  No.  7  North  Market 
street,  San  Jose.  [See  Report  State  Mining  Bureau  of  Cal., 
XII,  page  367;  XIII,  page  600.] 

Access  to  mine  refused  to  Field  Assistant. 

Wright  Mines. — These  lie  on  Llagas  Creek,  about  3  miles 
south  of  the  hacienda  of  New  Almaden,  25  miles  from  San 
Jose.  Mrs.  A.  Rodgers,  owner.  No.  1801  Leavenworth  street, 
San  Francisco.  [See  Report  State  Mining  Bureau  of  Cal., 
XII,  page  370;  XIII,  page  601.]  This  property  was  worked 
to  some  extent  in  former  years,  producing  some  good  ore;  but 
sufficient  work  has  not  been  done  in  later  times  to  judge  of  the 
possibilities  of  the  property. 


188  QUICKSILVER    RESOURCKS   OF   CALIFORNIA. 

STANISLAUS  COUNTY. 

Summit  Group  of  Mines. — These  consist  of  the  South  Summit, 
North  Summit,  Grayson,  Martin,  Hayward,  White  Oak,  and 
Hopkins  claims,  and  four  millsites,  in  Sees.  20  and  29,  T.  6  S., 
R.  5  E.,  principally  in  Stanislaus  Count}',  but  partly  in  Santa 
Clara  County,  on  Red  Mountain,  about  50  miles  from  San  Jose 
and  40  miles  from  Livermore.  The  Phoenix  Quicksilver  Min- 
ing Company,  owner;  H.  G.  Stevenson,  Hobart  Building,  San 
Francisco,  president;  E.  P.  Xewhall,  Deforest,  Santa  Clara 
Count}-,  superintendent.  [See  R.eport  State  Mining  Bureau  of 
Cal.,  XIII,  page  603.]  This  property  was  discovered  in  the 
70's  by  Mr.  Waterford,  who  turned  it  over  to  the  Martin 
Brothers,  of  Pleasanton.  The  Messrs.  Martin  worked  it  on  a 
small  scale  and  erected  a  5-ton  furnace  and  afterward  sold  it  to 
Mr.  A.  Hayward  and  associates,  who  recently  formed  the  com- 
pany which  is  the  present  owner.  It  is  opened  by  several  tunnels 
and  shafts,  which  show  that  there  are  three  distinct  zones  of 
mineralization:  The  Summit  vein,  having  a  strike  N.  15°  E., 
and  a  southeasterly  dip;  a  belt  of  sandstone,  having  a  north- 
westerly strike,  crossing  the  Summit  vein  (if  it  continues  past 
the  latter  is,  however,  not  yet  determined);  and  the  Gray- 
son vein,  having  also  a  northwesterh-  strike,  with  a  north- 
easterly dip. 

The  Summit  vein  is  developed  by  four  tunnels  and  a  shaft 
40  feet  deep  on  the  top  of  the  ridge.  The  vein  is  well  exposed 
in  tunnels  Xos.  i  and  2,  which  are  connected  by  an  incline 
shaft.  Considerable  understoping  has  been  done  in  Xo.  i,  and 
from  Xo.  2  a  shaft  has  been  sunk  first  verticalh-  until  it  reaches 
the  ioot  wall  and  then  along  the  foot  wall  at  an  angle  of  54°. 
The  vein  is  overlaid  by  "alta."  The  foot  wall  is  in  sandstone 
altered  by  silicification.  The  understopes  of  Xo.  i  on  the  foot 
wall  show  a  large  ore  body ;  one  crosscut,  40  feet  long,  has  not 
reached  the  overlying  "alta."  The  ledge  matter  is  a  serpen- 
tine, altered  into  an  opaline  rock.  The  cinnabar  is  remarkabl}^ 
disseminated  through  the  silica  in  fine  aggregates  of  cr3'Stals. 
Especially  in  the  upper  tunnel  a  great  portion  of  the  ore  is 
weathered  into  a  soft  ochreous  material,  due  to  the  oxidation 
of  the  iron  sulphides.  There  is  considerable  lime  in  the 
gangue.     The  Gravson  ledge  is  more  of  a  sandstone  character. 


STANISLAUS    COUNTY.  189 

with  cinnabar  coating  the  fracture  planes;  the  ledge  carries 
also  considerable  ochreous  material.  The  erection  of  a  50-ton 
furnace  is  contemplated.  The  manufacture  of  the  brick  for 
this  has  been  started. 

Adobe  Valley  Mine.— In  Sec.  24,  T.  6  S.,  R.  5  E.  The  Stanis- 
laus Quicksilver  Mining  Company,  owner;  H.  G.  Stevenson, 
Hobart  Building,  San  Francisco,  president;  E.  P.  Newhall, 
Deforest,  Santa  Clara  County,  superintendent.  This  property  is 
at  present  idle.  A  vertical  shaft,  about  180  feet  deep,  has  been 
sunk,  but  is  filled  with  water  to  just  below  the  100-foot  drift. 
The  country  rock  is  apparently  a  bedded  sandstone.  The  pres- 
ence of  considerable  black  clay  gouge  indicates  that  strong 
movements  have  taken  place.  The  rock  and  the  ledge  matter 
carr}'  a  great  amount  of  sulphur,  occurring  as  iron  and  mag- 
nesia sulphides,  and  where  these  have  been  decomposed,  as 
sulphates  and  free  sulphur.  The  sandstone  in  places  is  impreg- 
nated with  cinnabar,  associated  with  iron  sulphide,  but  the 
works  are  not  enough  advanced  to  admit  of  judging  about  the 
value  of  the  deposit. 

Orestimba  Mine. — This  is  on  Orestimba  Creek,  in  Sees.  25  and 
36,  T.  6  S.,  R.  5  E.  The  Hazard  Quicksilver  Mining  Company, 
owner;  H.  G.  Stevenson,  Hobart  Building,  San  Francisco,  presi- 
dent; E.  P.  Newhall,  Deforest,  Santa  Clara  County,  superin- 
tendent. The  property  is  at  present  idle.  A  short  tunnel  with 
several  crosscuts,  about  200  feet  above  the  creek  level,  shows 
that  the  country  rock  is  a  silicified  shale. 


OUTLYING   COUNTIES. 


EL  DORADO  COUNTY. 

Bernard  Mine.— This  is  in  Sec.  4,  T.  8  N.,  R.  lo  E.  The  Ber- 
nard Quicksilver  Company,  owner.  ly.  C.  Osteyee,  212  San- 
some  street,  room  11,  San  Francisco.  [See  Mon.  XIII,  U.  S. 
G.  S.,  page  384;  Report  State  Mining  Bureau  of  Cal.,  XII, 
page  359.]  This  property  was  first  developed  in  the  6o's, 
by  G.  Folger,  of  Jackson,  Amador  County,  under  the  name  of 
the  Amador  Quicksilver  mine.  The  present  owners  have  re- 
opened the  old  works,  which  consist  of  a  vertical  shaft  about 
75  feet  deep,  connecting  with  a  tunnel  about  65  feet  lower 
than  the  collar  of  the  shaft,  starting  on  a  southerh'  course, 
about  in  the  same  direction  as  the  strike  of  the  slate,  and  turn- 
ing nearl}^  at  right  angles  to  the  right  about  1 80  feet  from  its 
mouth.  Both  the  shaft  and  the  tunnel  are  entireh*  in  the  gray 
slates  of  the  Mother  Lode  region,  which  show  some  cinnabar 
on  panning.  After  passing  the  bend,  the  tunnel  crosscuts  the 
the  slates,  and  for  about  25  or  30  feet  the  walls  are  coated  with 
vermilion.  This  coating  appears,  however,  to  be  only  super- 
ficial, as  when  breaking  down  the  rock  no  signs  of  it  are  found 
on  the  new  fractures.  This  tunnel  being  very  old,  this  ver- 
milion may  be  a  recent  deposition.  About  a  quarter  of  a 
mile  west  of  these  works  a  belt  of  serpentine  runs  through 
the  countrj'. 

TRINITY  COUNTY. 

Surface  indications  of  quicksilver  ores  are  found  in  several 
places  throughout  Trinity  County,  but  active  mining  for  this 
metal  has  only  been  done  in  the  northeastern  part  of  the  county, 
between  Crow  Creek,  a  tributar}^  of  the  east  fork  of  Trinity 
River,  and  the  north  fork  of  the  east  fork  of  Trinity  River. 
The  surface  country  rock  of  this  section  is  principally  serpen- 
tine, which  is  generally  very  hard;  on  the  east  and  west 
ridge  forming  the  northern  boundary  of  the  basin  wherein  the 


TRINITY    COUNTY. 


191 


quicksilver  ore  bodies  occur,  a  great  amount  of  the  chr3-sotile 
variety  of  serpentine  is  found,  which,  however,  is  entirely 
absent  nearer  the  mineralized  section.  The  Emerald  tunnel 
cuts  through  the  formation  in  a  part  of  the  territory,  showing 
little  or  no  signs  of  mineralization,  hence  afiording  opportunity 


to  judge  about  the  rock  formation  of  the  country  in  general. 
It  starts  in  serpentine,  but  at  the  breast,  about  250  feet  in,  the 
material  is  a  diabase  altered  into  greenstone.  The  material 
wherein  the  ore  bodies  form,  being  also  altered  igneous  rock, 
it  is  ver}-  probable  that  the  serpentine  is  in  this  territory-  an 
alteration  product  of  igneous  rocks.  The  exposures  of  metamor- 
phics,  prominently  sandstones,  are  principally  located  west  of 
the  mineralized  zone,  on  the  slope  toward  the  North  Fork.    One 


192  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

small  exposure  of  igneous  rock  (quartz   porph5-r\^)  was  found 
near  Crow  Creek. 

The  material  wherein  the  ore  bodies  form  has  been  very 
much  altered;  it  is  probably  a  feldspar  porphyr}-.  Occasion- 
ally small  detached  exposures  of  croppings  are  found  in  the 
serpentine.  Thej-  have  an  ochreous  appearance,  and  their  rela- 
tion to  the  ore  bodies  developed  underground  is  as  yet  unde- 
fined. The  works  of  the  Altoona  mine  being  at  present 
inaccessible,  the  obser^^ation  of  the  underground  ore  appearance 
was  limited  to  a  depth  of  120  feet,  the  greatest  depth  at  which 
ore  bodies  are  developed  in  the  Integral  mine. 

Altoona  Mine. — This  lies  in  Sec.  22,  T.  38  N.,  R.  6  \V.,  and 
comprises  the  Trinity,  Altoona,  and  part  of  the  Blockade 
mining  claims.  The  Altoona  Quicksilver  Mining  Company, 
owner,  206  Sansome  street,  San  Francisco.  [See  Mon.  XIII, 
U.  S.  G.  S.,  page  366;  Report  State  Mining  Bureau  of  Cal., 
VIII,  page  643;  X,  page  716;  XII,  page  371 ;  XIII,  page  603.] 
The  Altoona  Quicksilver  Mining  Company  acquired  this  prop- 
erty in  1875,  but  prior  to  that  time  some  surface  work  had 
been  done  and  relatively  considerable  quicksilver  extracted. 
In  1879  the  mine  was  closed  down  by  litigation,  and  so 
remained  until  1894,  when  work  was  resumed,  a  Knox  & 
Osborne  fine-ore  furnace  erected,  and  the  underground  develop- 
ment work  energetically  pushed.  A  vertical  shaft  was  sunk 
to  a  depth  of  450  feet,  from  which  five  levels  were  driven;  in 
the  lowest  level  another  vertical  shaft  was  sunk  152  feet  deep, 
from  which  two  levels  were  driven.  In  all  there  are  seven 
levels,  covering  a  territor>^  of  1600  feet  in  a  northwesterly 
and  II 20  feet  in  a  northeasterly  direction;  within  which  four 
different  veins  were  worked  to  a  depth  of  about  600  feet. 
Three  of  these  veins  come  together  at  the  lowest  level,  forming 
a  mineralized  zone  about  400  feet  long  and  from  4  to  50  feet 
wide.  The  fourth  vein  has  no  connection  with  the  other,  and 
lies  about  400  feet  southwest;  it  has  been  worked  from  the 
third  (350  feet)  to  the  first  (140  feet)  level.  The  mine  makes 
a  very  large  amount  of  water,  requiring  several  large  pumps 
and  a  boiler  capacity  of  140  H.  P.  to  keep  it  unwatered,  causing 
a  high  cost  of  operation  per  ton  of  ore  worked;  and  when,  in 
1902,  part  of  the  reduction  plant  was  destroyed  by  fire,  the 
mine  was  shut   down,  and  the  water  stands  now  about  18 


TRINITY    COUNTY. 


193 


inches  above  the  floor  of  the  upper  level.  The  furnace  has 
lately  been  repaired,  and  the  material  of  the  dumps  is  run 
through  with  satisfactory  result. 

The  production  of  the  mine  has  been:  prior  to  1S75,  1500 
flasks;  from  1875  to  1879  (retorts),  8010  flasks;  from  1894  to 
1902  (furnace,  70  months),  19,671   flasks;  total   29,181   flasks. 

Carr  Mine* — This  is  in  Sec.  22,  T.  38  N.,  R.  6  \V.,  and  consists 
of  one  mining  claim.  G.  Carr,  of  Carr\'ille,  Trinity  County, 
owner.     Some  surface  work  of  no  consequence  has  been  done. 


PHOTO  No.  21.     ENTRANCE— CASTELT-A  DEVELOPMENT  TUNNEL,  INTEGRAL  MINE. 

An  exposure  of  croppings  is  found  on  this  mining  claim  in  the 
road  between  the  Altoona  and  Integral  mines. 

Integral  Mine. — This  is  in  Sees.  14,  15,  21,  22,  23,  27,  and  28, 
T.  38  N.,  R.  6  \V.,  and  consists  of  forty-six  mining  claims  and 
several  timber  sections.  The  Integral  Mining  Company, 
owner;  E.  W.  McGraw,  324  Pine  street,  San  Francisco;  Frank 
A.  Mahon,  superintendent,  Integral,  Trinity  County.  The 
geology  of  this  property  is  treated  previously  in  the  general 
description  of  this  district.     Some  croppings  are  found  between 


194 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


the  mouth  of  the  Castella  tunnel  and  the  sawmill,  but  no  ore 
bodies  have  been  cut  by  this  tunnel.  Serpentine  is  also  under- 
ground the  principal  country  rock.  In  this  serpentine  lies 
a  body  of  highly  altered  rock,  probably  an  altered  feldspar- 


Verr/ca/W/nze  b^ 
fween  40' a  80'/e/eL 


Probab/e  /imifs  of  porphyry  on  SO'/ei/el. 
"      ••        '•         ••/20'    •• 
Serpentine. 


„,         ,  freo) 
Blacksmifh 
shop 


Fig.  62a.     Underground  workings  of  Integral  Mine. 

porphyr>%  as  far  as  ascertained  in  the  form  of  an  irregular 
lens,  with  a  northwesterly  dip.  In  the  parts  of  the  lens  which 
carry  ores  the  material  is  thoroughly  decomposed  by  the  action 
of  the  mineral-bearing  waters,  which  deposited  there  in  iron 
and  mercury  sulphides,  the  former  being  largely,  if  not  entirely 


TRINITY   AND   OTHER    COUNTIES.  195 

weathered  into  iron  oxides,  decomposing  the  gangue  rock  and 
giving  it  a  yellow  and  black  color. 

The  principal  system  of  underground  works  consist  of  a 
shaft,  from  which  four  levels,  respectively  40,  80,  120,  and  180 
feet  below  its  collar  have  been  driven,  and  an  intermediate 
level  at  lOO  feet.  [See  Fig.  62a.]  The  180- foot  level  connects 
through  a  vertical  winze  with  the  Castella  development  tunnel, 
which  is  120  feet  vertical  lower;  and  from  this  winze  a  drift 
and  side  drift  have  been  run  25  feet  below  the  180- foot  level. 
By  connecting  the  points  where  the  serpentine  has  been  cut 
in  the  different  drifts  an  approximate  representation  of  the 
form  of  the  above-mentioned  lens  of  porphyry  containing  the 
ore  bodies  has  been  given.  A  great  amount  of  surface  work 
(assessment  work)  on  a  number  of  the  claims  has  been  done, 
without,  however,  disclosing  anything  of  importance.  The 
property  is  equipped  with  a  24-ton  fine-ore  Knox  &  Osborne 
furnace. 

Trinity  Mine. — This  consists  of  three  claims,  Trinitj'  Nos.  i, 
2,  and  3,  in  Sees.  21  and  22,  T.  38  N.,  R.  6  \V.  Messrs.  Riesch- 
ling,  owners. 

OTHER  COUNTIES. 

Besides  the  above  described  mines,  there  are  a  number  of  scat- 
tered cinnabar  deposits,  none  of  which  have  been  developed 
to  any  great  extent,  in  various  sections  of  the  State. 

In  Contra  Costa  County,  near  Mount  Diablo,  some  cinnabar 
has  been  found.      [See  Mon.  XIII,  U.  S.  G.  S.,  page  378.] 

In  Del  Norte  County  [see  above  cited,  page  366,  and  Report 
State  Mining  Bureau  of  Cal.,  XII,  page  198]  some  prospect- 
ing for  cinnabar  has  been  done  near  the  northern  border  of 
the  county  on  Diamond  Creek,  an  eastern  tributary  of  the 
north  fork  of  Smith  River.  The  Mercury-  group,  near  the 
mouth  of  Diamond  Creek,  is  owned  by  Israel  Dietrick  and 
others.  The  Diamond  Creek  group  lies  near  the  head  of  the 
same  creek,  close  to  the  State  line. 

In  Mariposa  County  a  cinnabar  occurrence  is  mentioned  by 
Professor  Whitney.  [See  Geological  Survey  of  California, 
vol.  I,  page  230.] 

13— QR 


196  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

In  Santa  Barbara  County  [see  Mon.  XIII,  U.  S.  G.  S.,  page 
382;  Report  State  Mining  Bureau  of  Cal.,  VIII,  page  537; 
X,  page  596;  XII,  page  366]  are  the  Los  Prietos  mines  in  the 
Santa  Ynez  range.  These  produced  in  former  years  some 
quicksilver,  but  have  been  idle  for  a  number  of  years.  Another 
occurrence  of  cinnabar  has  been  mentioned  near  the  Cuch- 
amma  River  (the  Eagle  Quicksilver  mine). 

In  Shasta  County  a  cinnabar  deposit  has  been  to  some  extent 
developed;  it  is  30  miles  northeast  of  Redding,  in  Sees.  4  and  5, 
T.  32  N.,  R.  I  W.  The  Clover  Creek  Cinnabar  Company, 
owner.     F.  P.  Primm,  president.  Redding. 

In  Siskiyou  County  [see  Report  State  Mining  Bureau  of  Cal., 
XII,  page  370;  XIII,  page  602],  near  Oak  Bar,  on  the  head- 
waters of  the  west  fork  of  Beaver  Creek,  in  the  northern  part 
of  the  county,  some  cinnabar  deposits  have  been  worked  to  a 
slight  extent  by  the  Siskij'ou  Quicksilver  Mining  Company 
(G.  V.  Snow,  president),  of  Oak  Bar;  the  company  has  also 
erected  a  small  furnace. 

The  Barton-Lange  is  another  property;  H.  J.  Barton,  owner, 
Oak  Bar.     Both  properties  are  non-producers. 

Some  cinnabar  was  found  in  the  sluice-boxes  of  the  hydraulic 
mines  in  Horse  Creek,  in  this  county. 


METALLURGY* 


The  subject  has  been  extensively  treated  by  Crookes  and 
Rohrig  in  "Practical  Treatise  on  Metallurgy,"  vol.  I  (1868); 
by  Kgleston  in  "The  Metallurgy  of  Silver,  Gold,  and  Mercury 
in  the  United  States,"  vol.  II  (1890);  also  by  Prof.  S.  B. 
Christy,  in  vols.  XIII  and  XIV  (i 884-1 886),  "Transactions 
of  the  American  Institute  of  Mining  Engineers,"  and  in  "The 
Imperial  Quicksilver  Works  at  Idria"  (1884),  by  the  same 
writer;  also  in  many  technical  papers,  among  which  the  "Min- 
ing and  Scientific  Press"  of  1878  and  1879,  giving  a  transla- 
tion of  Mr.  Kuss's  description  of  the  Almaden  mine  in  Spain; 
and  further,  in  many  European  technical  publications. 

The  scope  of  this  paper  is  a  statement  of  the  present  condi- 
tion of  the  quicksilver  industry  of  California,  and  hence  the 
older  methods,  no  longer  in  use  in  this  State,  and  those  used 
in  Europe  and  elsewhere,  will  only  be  alluded  to  where  neces- 
sary for  a  thorough  understanding  of  the  subject. 

The  extraction  of  mercury  from  ores  containing  sulphide  of 
mercury  and  occasionally  native  mercury  (the  only  forms 
wherein  mercurial  ores  of  commercial  importance  are  found) 
can  be  classified  as  the  metallurgical  process  of  distillation. 
It  is  accomplished  by  subjecting  the  ores  to  a  certain  degree  of 
heat,  applied  by  one  or  the  other  of  two  methods:  in  tightl}"- 
sealed  retorts,  wherein  the  ores  are  heated  without  coming  in 
direct  contact  with  the  products  of  combustion  of  the  fuel;  or 
in  large  furnaces,  where  the  heat  and  products  of  combustion 
of  the  fuel  pass  direct  into  the  ore  mass  and  are  carried  off 
with  the  heated  mercuric  vapors,  to  be  subsequently  condensed 
in  large  cooling  chambers.  The  retorts  are  generally  of  cast- 
iron.  The  Fitzgerald  furnace  may,  however,  be  classified  as  a 
continuous  brick  retort  furnace. 

The  essential  difference  in  the  two  methods  lies  in  the  fact 
that  the  vapors  given  off  by  the  ores  in  the  retort  furnaces  are 
separated  from  those  resulting  from  the  combustion  of  the  fuel. 

(197) 


19S  QUICKSILVER    RESOURCES    OF   CALIFORNIA. 

Professor  Christy,  in  his  exhaustive  study  on  Quicksilver  Con- 
densation [Transactions  American  Institute  of  Mining  Engi- 
neers, vol.  XIV.  page  237],  found  that  in  the  products  of 
combustion  of  an  average  furnace-day  at  New  Almaden,  run- 
ning on  3  per  cent  ore,  those  of  the  fuel  amount  to  nearly  80 
per  cent  of  the  total;  hence  the  fumes  from  a  retort  furnace  out 
of  which  the  mercun,-  must  be  separated,  are  much  smaller  in 
quantity  and  moreover  less  complicated  in  composition,  so  that 
the  liquefaction  of  the  mercury  is  rendered  much  easier  and 
less  costly.  The  theoretical  advantage  is,  however,  entirely 
obliterated  by  practical  disadvantages  which  restrict  the  use  of 
retort  furnaces  to  a  few  exceptional  cases.  Their  capacity  is 
small,  and  the  relative  labor  and  fuel  expense  consequently 
ven,-  high,  so  that  even  for  rich  ores  they  ofier  a  ver}-  unprofit- 
able method  of  treatment.  Unless  the  ores  are  ver>'  free  from 
iron  sulphide,  quicklime  must  be  added,  to  prevent  the  recombi- 
nation of  the  mercury  and  sulphur  in  vapor  form  at  the  mouth 
of  the  exit  pipe,  where  sudden  cooling  takes  place.  The  use 
of  retort  furnaces,  except  for  the  treatment  of  soot  and  of  con- 
centrates, maj'  as  a  rule  be  considered  bad  practice.  It  must 
be  acknowledged  that  their  erection  in  the  case  of  prospects 
and  new  mines  has  often  been  favored,  because  the  cost  of  con- 
struction is  low,  and  the}'  oSer  the  mine  owner,  who  has  only 
a  limited  capital  at  his  disposal,  the  chance  of  getting  some 
immediate  returns  out  of  his  mine.  This,  however,  is  done  at 
the  cost  of  the  future  of  his  property,  for  in  order  to  get  any 
results  he  is  forced  to  extract  onl)-  the  ver>-  rich  ore.  thereby 
very  materially  reducing  the  average  of  the  bulk  of  his  ore 
bodies.  Besides,  it  may  be  stated  that,  with  a  few  exceptions, 
the  products  of  those  retort  furnaces  have  scarcely  ever  paid 
for  the  work  of  extraction,  let  alone  that  of  the  development 
of  the  property. 

It  was  stated  previously  that  these  furnaces  might  be  prop- 
erly employed  for  the  treatment  of  concentrates.  In  the  text- 
books treating  on  this  subject,  it  is  generally  claimed  that: 
"The  attempts  of  mechanical  concentration  of  quicksilver  ores 
"  have  usually  not  been  successful,  because  the  cinnabar  is  so 
"  friable  that  a  greater  portion  floats  ofi  with  the  water." 
[Egleston,  above  cited,  page  804.]  Air.  G.  V.  Xorthey,  at  the 
Manzanita  mine,  in  Colusa  County,  has,  however,  been  \ery 
successful  in  concentrating  the  ore  of  that  mine.     The  ore  is 


METALLURGY. 


199 


first  crushed  rather  fine,  and  then  passed  through  a  5-foot 
Huntington  mill.  [See  Fig.  63.]  The  pulp  passes  through  a 
concentrating  plant,  having  a  capacity  of  from  i  to  2  tons  per 
hour,  depending  upon  the  gangue.  The  plant  consists  of  five 
bumping-tables,  the  pulp  going  first  to  one  table  and  from  this 
is  divided  over  the  four  other  bumping-tables.  The  tailings 
are  elevated  and  sized.     The  heavier  pass  over  a  Bartlett  con- 


Plan  and  e/eyat/on  of    Concentrating     System. 

Manzanita    Mine . 
a= Crusher 

b'-Huntington  /»////  (^Ty^ 

c,ci=  Bumpirfg  Tables 

e=  Tailings  Concentrators  1 f^*'    ^^^^s^^\s^'^ 

/  =  Eievator 


r  I 


r=t 


3\ ■!:: 


C 

' " 

e_ 


D 


centrator,  and  the  lighter  over  a  belt  vaimcr  without  side  shake. 
This  plant  is  driven  by  a  25-horsepower  Harding  distillate 
engine,  using  15  gallons  of  distillate  per  twelve  hours,  laid 
down  (including  28  miles  teaming  from  Williams)  at  20  cents 
per  gallon,  or  $3  per  twelve  hours.  The  plant  requires  one 
concentrator  and  two  helpers. 

The  concentration  varies  according  to  t'.ie  amount  o:   iron 


200 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


pyrites  in  the  ore.  When  the  latter  are  scarce  it  may  reach  a 
high  figure,  but  generally  the  concentration  will  be  about  20 
to  I.  When  high  in  iron  pyrites  the  concentration  ratio  will 
be  too  low  to  produce  a  material  which  can  be  profitably  handled 
in  a  retort  furnace. 

The  concentrates  are  dried  and  retorted  in  a   lo-pipe  retort 


PHOTO  Xo.  22.  PIPE  RETORT  FURNACE.  M.A.NZAXIT.\  MINE,  COLUS.A^  COUNTY 

furnace,  which  has  some  features  worth  noting,  [See  Fig.  64.] 
B}'  using  arches  around  the  pipe  spaces,  each  retort  can  be 
taken  out  separately  without  interfering  with  the  working  of 
the  others.  Each  retort  has  a  separate  mercury  outlet,  allow- 
ing opportunity  to  judge  about  its  workings,  and  the  water 
circulation  through  each  water  jacket  can  be  regulated  sepa- 
rately. The  firebox  is  placed  to  the  side  of  the  first  retort, 
instead  of  under  it,  enabling  the  easy  discharging  and  charging 


METALLURGY, 


201 


of  this  retort.  B}'  placing  the  door  of  the  retort  inside  the 
wall,  cooling  of  the  space  against  the  door  and  consequent 
accumulation  of  mercury  at  that  point  are  prevented.     The 


charge  is  from  75  to  80  pounds  of  concentrates  per  shift,  with 
the  necessary  lime,  against  150  pounds  of  raw  ore.  Two  fur- 
nace men  are  required — one  per  shift. 

The  expenses  of  this  plant  are  about  $25  per  day  for  labor, 


202 


QUICKSILVER    RESOURCES   OF    CALIFORNIA. 


fuel,  repairs,  etc.  The  lo-pipe  retort,  with  suitable  ore,  can 
handle  the  total  product  of  the  concentrating  mill,  running  day 
and  night,  concentrating  from  20  to  24  tons.  The  total  cost 
of  the  plant,  not  including  the  mill  building,  is  approximatel3': 

25  H.  P.  engine $1,000.00 

Rock-crusher 250.00 

5-foot  Huntington  mill 1,500.00 

5  bumping-tables     1,000.00 

Concentrating  table 500.00 

I  elevator 100.00 

Fittings,  pipes,  etc 150.00 

Contingent  expenses 500.00 


I  pipe  retort,  with  building  and  drier 


$5,000.00 
.   2,000.00 

$7,000.00 


j7,uou.uu 

This  plant  in  three  months  turned  out  330  flasks  of  mercurj-; 
^  / / 1.  i 


4  I ron  pipe   from  re/ort 


Fig.  65.    Condensing  plant  soot  retort,  Boston  Mine. 

and  since  the  visit  of  the  writer,  has  continued  to  be  operated 
with  about  the  same  results. 

This  pipe  retort  furnace  may  be  considered  as  an  example  of 
the  best  practice  for  such  an  installation  •  the  condensing  prac- 
tice is  especially  very  well  conceived. 

At  the  Boston  mine  (Knoxville),  the  soot  is  treated  in  a 
retort  furnace  using  a  condenser  formed  b}'  a  wooden  box, 
surrounded  by  water,  which  is  constant!}^  renewed,  the  exit 
pipe  from  the  condenser  being  partly  immersed  in  the  water 
covering  the  top  of  the  condensing  box.      [See  Fig.  65.] 

Another  arrangement  of  flues  under  the  pipe  retorts,  by 
which  the  parts  of  the  pipes  nearest  the  front  and  back  walls 
receive  the  greatest  heat,  has  been  patented  by  Messrs.  Johnson 
and  McKay.  [See  Fig.  66.]  The  exit  pipes  of  these  furnaces 
are  only  6  feet  long,  without  any  attempt  at  cooling;  under 


METALLURGY. 


203 


their  lower  end  runs  a  wooden  trough  wherein  the  mercury  is 
collected,  and  a  loose  burlap  sheet  is  thrown  over  the  end  of 
the  pipes  and  the  trough.  Whether  this  installation  suffices 
to  condense  all  the  mercury  vapors  is  very  doubtful. 

Two  different  forms  of  cast-iron  retorts  are  used.  The  pipe 
retorts  vary  from  lo  to  12  inches  in  diameter,  and  from  7  to  9 
feet  in  length,  those  of  12  inches  diameter  being  generally  the 
shortest.  Their  capacity  is  then  from  5.22  to  5.9  cubic  feet. 
There  must  be  left  sufficient  space  in  the  retort  so  that  during 
the  roasting  process  a  sufficient  amount  of  free  oxygen  will  be 
present  to  carry  off  the  other  vaporized  products  outside  of  the 
mercury.  Professor  Christy  [above  cited,  vol.  XIV,  page  236] 
calculates  that  i  kilogram  of  ore,  containing  0.75  kilogram  of 
faxed  material  and  carrying  3  per  cent  of  quicksilver,  requires 
0.067    cubic   meter  of    air  at  0°  C.  and  760  mm.   pressure  in 

JOHNSON  a    M^  KAY 
FURNACE 


ltl///llllri}l,},l,,,,,Tr7r, 


order  to  carry  the  sulphur  off  as  sulphur  dioxide,  or  at  the  heat 
in  the  retorts,  which  can  be  placed  at  100"  C.  when  charging, 
v^=v^  (i+cz  /);  7'  =  o.o67  (1+^^^)^0.091  cubic  meter,  which 
reduced  to  pounds  and  feet  gives  for  i  pound  of  ore,  1.46  cubic 
feet  of  air.  In  most  cases  the  ores  carry  sufficient  iron  sul- 
phides to  make  the  addition  of  some  quicklime  very  advisable, 
which  will  absorb  the  freed  sulphur,  according  to  the  equation, 
4  HgS  +  4CaO  =  4Hg+3CaS  +  CaO,  vSOa.  The  sulphur  freed 
from  the  reduction  of  the  iron  sulphides  to  ferrous  sulphide 
(FeS.=  FeS-f-S)  will  also  be  absorbed  by  the  quicklime.  The 
preceding  indicates  that  the  practice  of  filling  the  retorts 
almost  completely  with  ore  is  wrong;  a  charge  of  about  150 
pounds  of  ore,  filling  about  one  third  of  the  retort,  is  the  most 
preferable.  The  retorts  must  be  kept  at  a  relatively  low  heat, 
not  exceeding  that  required  for  the  volatilization  of  the  mer- 
cury, from  375°  to  400*^  C.  (  =  750'^  Fahr. ).  The  distillation 
of  cinnabar  (HgS4-20  =  HgH-SO,)  takes  place  at  about  360°  C. 
[Crookes  and  Rohrig,  above  cited,  page  505.] 


204 


QUICKSILVER    RESOURCES   OF    CALIFORNIA. 


The  charge    generalh-  remains  twelve  hours  in  the  retort, 
but  at  the  Helen  mine,  Mr.  Rocca    has  found  that  with  his 


highh-  pyritiferous  and  rich  ore  he  obtained  better  results  by 
leaving  the  charge  twenty-four  hours  in  the  retort  and  keeping 
the  heat  at  its  lowest  limit. 


METALLURGY. 


205 


The  Ch  retorts  are  generally  i8  inches  wide  and  12  inches 
high  in  the  center,  giving  them  an  area  of  i  square  foot,  and 
from  7  to  9  feet  long.  Their  charge  capacity  is  consequently 
larger.  Their  cost  is  also  much  higher — $200  apiece,  against 
$25  for  a  pipe  retort. 

The  opinions  of  quicksilver  operators  differ  very  much  on 
the  relative  merits  of  pipe  retorts  and  q  retorts,  both  having 
their  adherents;  but  for  soot  furnaces  those  of  the  q  retorts 
are  probably  in  the  majority. 

Mr.  C.  Fitzgerald  has  applied  the  principle  of  heating  the 
ore  without  bringing  it  into  direct  contact  with  the  products 
of  combustion  of  the  fuel  to  a  continuous  retort  furnace.  [See 
Fig.  67.]  This  furnace  con.sists  of  an  inclined,  arched  channel 
of  firebrick  (angle  35°)  with  a  tile  floor.  It  has  a  charging 
hopper  at  the  upper  end  and  a  discharge  chamber  with  door  at 
the  lower  end.  The  flames  from  the  fire  chamber  pass  under 
this  ore  chamber  along  two  center  flues,  return  along  two  out- 
side flues,  pass  to  the  top  of  the  arch  at  the  lower  end,  and  go 
from  the  upper  end  to  the  smokestack.  The  vapors  from  the 
ore  chamber  are  conducted  through  an  iron  exit  pipe,  which 
is  placed  near  the  upper  end  of  the  ore  chamber  and  is  water- 
jacketed  outside  of  the  furnace,  to  two  condensers.  In  the  sec- 
ond condenser  an  air  current  for  exhaust  is  created  by  a  water 
spray  under  100  feet  pressure,  working  on  limestone  to  catch 
the  flour  mercury.  The  capacity  of  each  chamber  is  rated  at 
10  tons  per  twenty-four  hours,  using  one  cord  of  pine  wood.  In 
practice  the  capacity  is  less.  Three  of  these  furnaces  have  been 
lately  erected — one  at  the  Culver-Baer  mine,  one  at  the  Uncle 
Sam  mine,  both  in  Sonoma  County,  and  one  at  the  Aurora 
mine,  San  Benito  County. 

The  reduction  of  quicksilver  ores  on  a  large  scale  is  con- 
ducted in  California  in  shaft  furnaces.  The  evolution  of  these 
furnaces  from  the  primitive  forms  can  be  found  in  detail  in  the 
above-mentioned  metallurgical  works.  Suffice  to  say  that  at 
present  continuous  furnaces  are  exclusively  used.  They  may 
be  subdivided  into  coarse-ore  and  tile  furnaces,  the  former  only 
treating  lump  ore;  the  latter  medium-sized  and  fine  ores. 

A  reduction  plant  may  be  divided  into  two  parts:  the  fur- 
nace and  the  condensing  plant.  The  latter  is  just  as  impor- 
tant as  the  former.  The  requirements  of  a  good  furnace  are: 
that  it  burns  the  rock,  that  is,  that  all  the  quicksilver  is  elim- 


206  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

inated  from  the  ore  when  said  ore  is  discharged  and  thrown 
over  the  dump;  that  the  charging  be  done  in  such  a  manner  as 
not  to  allow  the  escape  of  any  considerable  portion  of  the 
fumes,  thus  preventing  loss  in  mercury,  and  especially  danger 
to  the  health  of  the  employes;  and  finally,  that  the  furnace  does 
its  work  with  a  reasonable  consumption  of  fuel. 

The  main  portion  of  the  masonry  of  a  quicksilver  furnace 
is  built  of  ordinary  brick.  The  furnace  of  the  Corona  mine 
in  Napa  County  is  an  exception,  being  built  of  tufa  instead  of 
common  brick.  Only  those  parts  which  are  exposed  to  the 
action  of  the  fire  and  the  products  of  combustion  are  lined  with 
firebrick.  The  common  bricks  are  generally  burned  on  the 
spot,  and  very  often  the  operators  accept  and  build  their  fur- 
naces with  very  inferior  material,  the  result  being  that  even 
when  dried  and  heated  with  the  greatest  care,  large  cracks 
appear  in  the  furnace,  which  are  not  only  detrimental  to  the 
regular  march  of  the  furnace,  but  cause  a  great  decrease  in  its 
quicksilver  production,  which,  it  is  true,  is  not  a  complete  loss, 
as  the  metal  forms  in  the  furnace  bricks  as  native  metal  and 
cinnabar  and  can  be  recovered  after  tearing  down  the  furnace, 
but  which  still  is  a  very  unprofitable  metallurgical  treatment. 
Another  cause  of  rapid  deterioration  of  furnaces  is  found  in  too 
rapid  driving,  which  can  only  be  obtained  by  raising  the 
temperature  in  the  furnace,  generally  to  a  degree  which  will 
destroy  in  a  relatively  short  time  the  refractory  material  used 
in  the  furnace  construction  in  those  parts  most  exposed  to  the 
high  heat  of  the  flame.  From  the  data  given  subsequently  on 
furnace  practice,  it  will  be  seen  what  a  great  difference  there 
is  between  the  time  the  ore  remains  in  the  furnace  in  different 
reduction  works. 

As  in  all  other  metallurgical  processes,  the  end  to  be  obtained 
is  not  perfection  from  a  metallurgical  standpoint,  but  from  a 
commercial  standpoint.  As  in  a  gold  mill  it  is  often  good 
practice  to  neglect  the  extraction  of  a  small  percentage  of  gold 
out  of  the  ore,  so  in  furnace  practice  the  amount  of  ore  passing 
through  the  furnace  and  the  amount  of  fuel  used  must  be 
governed  bj^  the  condition  of  obtaining  the  largest  results  at 
the  lowest  cost  per  unit  of  produced  metal.  This  depends  to  a 
great  measure  on  the  special  conditions  existing  in  different 
plants. 

It  may  be  here  stated  that  the  superintendence  of  a  quick- 


PHOTO  No.  L'3.  CORONA  FURNACE. 


PHOTO  No.  24.  TUFA  FURNACE  IN  COURSE  OF  CONSTRUCTION,  CORONA 
QUICKSILVER  MINE. 


208  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

silver  reduction  plant  requires  a  great  amount  of  technical 
knowledge,  both  practical  and  theoretical,  and  a  constant 
personal  super\-ision ;  to  put  such  a  plant  in  the  hands  of  any- 
bod}'  who  is  not  thoroughly  competent  will  invariably  lead  to 
disappointment  and  financial  loss. 

The  coarse-ore  furnace  is  simplj-  a  shaft  in  which  the  ore  is 
dumped  from  the  top,  extracted  at  the  bottom  and  heated 
directly  by  the  flame  from  the  fireplace,  the  products  of  com- 
bustion passing  through  the  ore  column.  The  lumps  vary  in 
diameter  from  3/^  to  9  inches.  Various  types  of  these  furnaces 
are  at  present  in  operation. 

Exeli  Continuous  Furnace. — This  furnace  was  first  introduced 
in  1 87 1  at  Idria,  Austria,  b}-  Bergrath  A.  Exeli.  Two  of  these 
furnaces  are  in  use  at  Xew  Almaden — furnaces  Xos.  7  and  9. 
Fig.  68  represents  this  type  of  furnace,  of  which  a  ver}-  complete 
description  is  given  by  Egleston  [above  cited,  page  85 7]  and 
S.  B.  Christy  [above  cited,  vol.  XIII,  page  561].  These  iron- 
clad furnaces,  built  in  1874  and  1875,  are  still  in  operation, 
treating  1 2  tons  of  ore  ever}'  twent3'-four  hours;  the  ore  remains 
forty-eight  hours  in  the  furnace.  While  it  is  generally  taken 
for  granted  that  ores  carrjdng  a  great  amount  of  metallic 
mercury  can  not  well  be  handled  in  shaft  furnaces,  these  two 
furnaces  in  former  j-ears  gave  verj'  satisfactory  results  when 
burning  the  ore  from  the  1500-foot  level,  Randol  shaft,  which 
contained  large  quantities  of  native  mercur5\  The  charge  con- 
sists of  about  1600  pounds  of  ore.  These  two  furnaces  require 
two  men  per  shift,  and  burn  each  0.605  cord  of  wood  per  twenty- 
four  hours.     The  cost  of  treatment  per  ton  is : 

Labor $0.4166  (') 

Fuel 0.3025  (^) 

Total J0.7191 

/   \   4Xt2.so     »        ti/L      I   \    o.6o5X$6.oo     . 

(i)  :lrl£—5_.  =$0.4166      (2)  ^^^^ =  K).3025 

24  12 


IRON  CLAD  SHAFT  FURNACE 

(CONTINUOUS) 


SECTION  A  B 


ELEVATION 


HORIZONTAL  SECTIONS. 

Fig.  68.    Exeli  Furnace.    Scale  \i"=i'. 


210  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

Knox-Osborne  Coarse-Ore  Furnace. — This  furnace  was  patented 
in  1872.  [See  Fig.  69. J  Formerl}-  a  number  of  these  furnaces 
were  in  use,  but  in  later  years  their  number  has  been  greatly 
reduced.  One  furnace  is  in  use  at  the  Manhattan  mine  (Knox- 
ville),  and  the  old  furnace  at  the  Cerro  Bonito  mine,  San  Benito 
County,  has  been  renovated.  [For  description,  see  Egleston, 
above  cited,  page  841.] 

Some  fine  ore  can  be  charged  with  the  lump  ore,  but  only 
sparingly,  other^'ise  it  will  choke  up  the  passages  between  the 
lumps,  through  which  the  products  of  combustion  of  the  fuel 
must  freely  circulate.  The  inventor  ob\dated  this  by  adding 
some  pieces  of  wood  to  the  fine  ore  when  much  of  this  material 
was  contained  in  the  charge,  but  this  did  not  fully  obviate  the 
trouble ;  and  besides,  the  addition  of  fine  ores  materially  reduces 
the  daily  capacity  of  the  furnaces.  Consequenth',  since  the 
general  introduction  of  the  tiled  furnaces,  only  coarse  ore  is 
charged  into  the  various  coarse-ore  types  of  shaft  furnaces. 
The  cubic  content  of  the  furnaces  is  about  75  tons,  and  as  it 
handles  about  24  tons  per  da}-,  the  ore  remains  about  three  da3's 
in  the  furnace.  The  wood  consumption  on  coarse  ore  is  from 
one  to  one  and  a  half  cords  of  oak  per  twenty-four  hours. 
Three  men  per  shift  are  required. 

Luckhardt  Continuous  Coarse- Ore  Furnace. — This  furnace  was 
used  in  former  years  at  several  mines,  but  at  present  none  are 
working  in  California.      [See  Egleston,  above  cited,  page  838.] 

Neat*s  Coarse-Ore  Furnace. — Patented  by  John  Neat.  [See 
Fig.  70.]  Two  of  these  furnaces  are  at  the  St.  John  mine,  Solano 
County.  This  furnace  has  no  fireplace.  The  ore  is  charged  with 
coke  in  alternate  layers,  using  from  3^^  to  4  per  cent  of  coke, 
depending  on  the  draft  in  the  furnace.  The  drawing  space  in 
the  bottom  of  the  furnace  is  open,  leaving  access  to  the  air 
and  furnishing  the  draft.  The  top  of  the  furnace  consists  of 
a  hopper,  with  doors  at  the  bottom,  moved  by  levers  from  the 
charging  floor.  At  this  floor  there  is  besides  a  cover  with  a  water 
seal,  and  provided  with  a  glass  panel  to  judge  of  the  condition 
of  the  charge.  When  the  latter  is  at  red  heat  a  charge  is  with- 
drawn from  the  bottom.  This  is  done  bj^  withdrawing  the 
fork  (c),  resting  on  the  bar  {d).  The  drawing  is  done  at  inter- 
vals varying  from  i^  to  2}(  hours,  according  to  the  draft, 


-D 


I     ' 


Hat=ii 


Lk 


'Mill  I  I 


iffiTitTTiTni-nTiirniii-nifTTiirftTT^  '.; 


imn  111111111 


14— QR 


212 


OUICKSILVER    KESOURCES    OF    CALIFORNIA. 


which  is  dependent  upon    atmospheric    conditions.     The    ore 
must  be  in  pieces  of  i}^  inches  or  over.     Judging  from  the 


Charging  Hopper 


^^. 


>^ 


^c/ 


/ran  p/afe  f/oor 


Discharging    Fork    and 
Door. 


COARSE   ORE  FURNACE. 

JOHN     NEA  TS'      RAT. 


furnace  dump,  a  certain  amount  of  clinkering  takes  place  in 
the  furnace. 


METALLURGY. 


213 


New  Idria  Coarse-Ore  Furnace* — [See  Fig.  71.]  This  furnace 
has  been  designed  by  Mr.  B.  M.  Newcomb,  the  general  superin- 
tendent of  several  of  the  principal  quicksilver  mines  in  the  State. 


\ 

>' 

*^o 

^Q 

J           ' 

/• 

-) 1 

-^ 

J 

Su/ptjffff     - 

.\ 

T 

X 

J             ^ '■ 

V 

Cc: 

V^'l 

~) 

^j'^:. 

\ 

^ 

7---' 

I 


As  will  be  seen  from  the  sketch,  the  fire  is  applied  on  both 
sides  of  the  charge,  which  is  only  4  feet  through,  and  6  feet 
long  in  each  compartment  at  the  level  of  the  top  of  the  fire 
chambers,  and  is  heated  at  three  sides,  while    besides,  as   it 


214 


QUICKSILVER    RESOURCES   OF    CALIFORNIA. 


comes  .nto  the  fire 
chambers,  the  charge 
spreads,  thus  causing 
its  speedy  heating  to 
the  highest  tempera- 
ture in  the  furnace. 
The  depth  of  the  dis- 
charge doors  below 
the  level  of  the  fire 
chamber  gives  the  ore 
a  chance  to  cool  off, 
and  to  give  off  the 
mercury  vapors  not 
volatilized  during  its 
passage  in  front  of  the 
fire  chamber.  This 
furnace  is  17  feet 
wide,  24  feet  through 
at  the  level  of  the  fire 
chamber,  and  has  a 
total  height  of  42^^ 
feet  from  drawing 
floor  to  charging 
track.  It  handles  from 
90  to  100  tons  per 
twenty-four  hours;  its 
cubic  capacity  is  2400 
feet,  hence  the  ore 
remains  a  little  above 
twenty-four  hours  in 
the  furnace.  It  is 
run  by  two  shifts  of 
five  men  each — one 
furnace  man,  two 
chargers,  and  two 
drawers — and  requires 
not  quite  2 '  -  cords  of 
wood  per  day.  The 
excessively  low  fuel 
consumption  is  parth' 
due  to  the  high  per- 
centage of  iron  sul- 
phide in  the  ore. 


METAIJ.rRGV. 


215 


The  fine-ore  furnaces  belong  nearly  all  to  the  tile  furnace 
type,  with  the  exception  of: 

Livermore  Furnace. —  [See  Fig.  72.]  Only  two  of  these  fur- 
naces are  at  present  in  operation — one  at  the  Cloverdale  mine, 
the  other  at  the  Culver-Baer  mine,  both  in  vSonoma  County. 
The  latter  is  a  reconstructed  Fitzgerald  furnace.  For  more 
detailed  description  of  this  furnace,  see  Egleston,  above  cited, 
page  887. 

The    tile    furnaces  generally  adopted  in  California  are  the 


Fig.  72.     Longitudinal  section.     Modified  I.iverinore  quicksilver  furnace. 

Litchfield,  the    Knox  &  Osborne    fine-ore;  and  the    Hiittner 
Scott. 

Litchfield  Furnace  has  been  in  operation  at  the  Great  Western 
mine,  Lake  County,  for  a  number  of  years,  and  has  given 
good  satisfaction,  although  admittedly  consuming  more  fuel 
than  the  Hlittner-Scott  furnace.  It  resembles  closely  the  lat- 
ter, except  that  the  heat  ascends  in  the  ore  chambers  between 
the  walls  and  the  tiles,  instead  of  being  forced  to  pass  over  the 
tiles. 

Knox-Osborne  Furnace»  for  fine  ore,  is  used  in  the  Manhattan, 
Altoona,  and  Integral  mines.  This  furnace  has  a  capacity  of 
24  tons  per  day.  It  consists  [see  Fig.  73]  of  two  ore  chambers, 
across  which  the  inclined  tiles  are  placed  in  a  checkerboard 
manner;  the  two  upper  rows  of  tiles  are  of  cast-iron,  the  others 
of  fire  clay.  The  ore  glides  down  along  the  channels  formed 
by  the  inclined  places.     The  double  fire  chamber  is  at  one  side 


^.F- 


H-f 


.9  €/ 


PHOTO  No.  26.     CLOVERDALE  REDUCTION  PLANT. 


PHOTO  Xo.  JT.     GRK:A  r  WKSTEKX  (jriCKSILVER  MINING  CO    REUl'CTION  PLANT. 


218 


QUICKSILVEU    RESOURCES    OF    CALIFORNIA. 


of  the  ore  chamber.  The  partition  walls  between  the  fire 
chamber  and  the  first  ore  chamber,  between  the  ore  chambers, 
and  between  the  second  ore  chamber  and  the  first  dust  cham- 
ber, are  pierced  with  pigeon  holes,  through  which  the  flames 
pass,  heating  the  tiles  and  the  ore.  The  partition  wall  between 
the  first  and  second  dust  chamber,  both  of  which  form  an 
integral  part  of  the  furnace,  has  five  openings  3  feet  high  on 
the  level  of  the  floor  of  the  fireplace,  creating  a  down  draft 


PHOTO  No.  28.     MANHATTAN  FURNACK. 

in  the  furnace.  The  second  dust  chamber  is  provided  in  its 
outer  wall  with  a  large  opening  near  the  top,  through  which 
the  fumes  pass  into  the  first  condenser,  which  is  built  at  the 
Integral  mine  contiguous  to  the  furnace.  The  top  of  the  fur- 
nace is  open ;  the  charge  is  placed  directl}^  on  the  upper  rows 
of  tiles;  the  down  draft  above  mentioned  being  deemed  suffi- 
cient to  prevent  the  escape  of  gases  from  the  furnace. 

Huttner-Scott  Furnace,— [See  Fig.  74.]  This  furnace  repre- 
sents the  latest  evolution  of  quicksilver  furnaces  in  California. 
Originally  only  used  for  fine  ores,  it  has  been  modified  to  burn 


METALLURGY. 


221 


Fig.  75.     Tiling  of  Furnace  Xo   3.  New  Alniaden. 


also  medium-sized  ore,  up  to  3 '2  inches.  It  is  extensively 
described  and  discussed  by  Egleston  [above  cited,  page  864] 
and  Christy  [above  cited,  vol.  XIII,  pages  553  and  566].  The 
tiles  form  a  zig- 
zag plane,  along 
which  the  ore 
fed  from  the  top 
slides  down 
through  the  fur- 
nace until  finally 
discharged  at  its 
bottom  through 
the  drawing  pit, 
being  gradually 
heated  on  its  de- 
scending course. 
The  size  of  the 
ore  lumps  which 
can  be  treated  in 
this  furnace  is  governed  by  the  distance  between  the  edge  of 
one  shelf  to  the  face  of  the  next  below  it,  called  the  shelf-slit. 
This  distance  was  3  inches  in  the  first  furnaces.  Since  then 
it  has  been  increased;  the  general  dimensions  now  used  is 
5  or  6  inches,  allowing  medium-sized  ore  to  be  charged.  In 
furnace  No.   i,  New  Almaden,  built  in   1880,  the  shelf-slit  is 

8  inches,  the  largest 
'^  used  in  any  furnace 
^  of  this  type. 
'^      Generall)-  the  tiles 
'Z  are  flat;  their  largest 
^  commercial     dimen- 
'^  sions    are    3    inches 
by  15  inches  by  36 
^  inches.  They  are  im- 
ported, and  cost,  laid 
down  in  San  Fran- 
cisco,   $3.50    apiece. 
Larger  tiles,  or  those  of  special  form,  cost  more.     The  detail 
sketch  shows  the  manner  in  which  the  tiles  are  secured  in  the 
ore  chamber. 

Furnace  No.  3,  New  Almaden,  has  a  different  form  of  tiles. 
[See  Fig.  75,  and  \ol.   XIII.  above  cited,  page  575.]      These 


Tiling  oT  Cerniak-Spirek  furnace. 


222 


ouicksilvp:r  kesoukces  of  California. 


tiles  have  not  proven  as  satisfactory  as  the  flat  ones.  In  Europe, 
however,  a  similar  form  of  tile  is  commonly  used  in  the  Cermak- 
Spirek  furnace.      [See  Fig.  76.] 

All  the  Hiittner-Scott  furnaces  have  the  lire  chambers  on 
one  side  of  the  ore  chambers,  and  a  vapor  chamber  on  the  other 
side,  except  the  Wide  Awake  furnace  at  Sulphur  Creek.  Colusa 
County,  where  a  fire  chamber  is  placed  on  lioth  sides  of  the  ore 


PHOTO  Xo    3,1.     FURXACK  PLANT.  IXTEGKAL  MIXE.  TKINirV  COUXTY. 

chamber.  Mr.  Gibson  claims  that  thereby  the  capacity  of  the 
furnace  is  materially  increased  without  increasing  the  fuel 
consumption.  Mr.  Robert  Scott  is  of  the  opinion  that  one  set 
of  fire  chambers  is  sufficient  to  heat  the  ore  which  can  be  put 
through  the  furnace  to  the  required  temperature. 

The  Hiittner-Scott  furnaces  are  made  of  various  capacities, 
which  are  governed  by  the  number  of  ore  chambers  in  the 
furnace,  and  by  the  height  of  each  ore  chamber.  Following  is 
a  table  giving  the  dimensions  of  some  furnaces: 


METALLURGY. 


223 


s-inoH 


-2  °        '. 


>!?    is? 


■jaqtunx 

Hex-  a 


^    . 

c 

S 

1§§  1 

^K< 

a  2 

u  c 

Sx 

nt 

til  SlIIBUIdH 

aSJBij^  ajiiij. 

■XjpBflB^ 


•jndino  XjiBa 


'j:^       r:c        tr,       r^       fr.      ^ 


S.      f^         rO         Tf         ■*         ro 


■s::^         is? 

.V    ir,       -r       ■*       t»      o 


■t;:^;   :s   ;se  <:  S2 

.J>    t^       M        o        0>       CO      >0 

<,    -        -        "  •-        - 


^  ^ 


to         W         \0  to         M        ^2 


2    5    a    s, 


.:^      j^      j^       ^  ^ 
—       —       _       ^  u 


x.    /.    y.    y.    £    ~    p. 


r     •:     -    3.    a    ai; 
-     /^     r.     -x     «;     O 


224 


QUICKSILVER    RliSOURCES    OF    CALIFORNIA. 


At  the  New  Almauen,  some  furnaces,  viz.,  Xos.  3  and  S,  are 
entirely  surrounded  by  iron  plates,  and  are  called  "ironclad 
furnaces."  This  method  of  inclosing  a  furnace  gives  very  good 
satisfaction,  but  is  very  expensive.  Generally  furnaces  are 
inclosed  in  a  wooden  framework  strengthened  by  iron  tie  rods. 
In  order  to  prevent  this  wooden  framework  from  catching  fire, 
especially  near  the  cracks  in  the  furnace,  which  are  almost 
inevitable,  it  is  advisable  to  surround  them  with  asbestos,  2 


t     " 

PHOTO  No.  31.     K.-VRL   FrR.\.\Cl..   r-AX   LUIS  OBISPO  COUNTY 

inches  thick.  [See  Fig.  84.]  The  later  furnaces  are  commonly 
of  a  daily  capacity  of  10,  20,  30,  and  50  tons.  The  principal 
materials  entering  in  these  furnaces  are: 

lo-Toii.  i)o-Toii.  so-Tou. 

Common  brick No.      150,000         300,000         400,000 

Firebrick "  12,000  20.000  30,000 

Tiles    "  iSS  360  42S 

Cement bbls.  25  40  50 

Fire  clay. 

Timber  for  frame. 

Iron  for  frame,  grates,  hopper ^  etc. 


METALLURGY. 


225 


The  price  of  the  firebrick  is  $32.50  per  1000  at  San  Francisco. 
The  price  of  tiles  3  inches  by  15  inches  bv  36  inches  is  S3. 50 
apiece. 

When  the  ore  is  charged  moist  in  the  furnace  a  great  amount 
of  water  vapor  will  be  formed,  which  not  only  increases  the 
already  excessive  amount  of  fumes  out  of  which  the  mercury 
must  be  condensed,  but  also  the  formation  of  a  great  amount 
of  sulphuric  acid  and  of  sulphates,  both  of  which  are  very 
injurious  to  the  condensers.     The  opinion   of  operators  as  to 


}-"lG    77.     Ore  Drier,  Utilizing  exhaust  Ml  uiii 

the  desirable  degree  of  dryness  of  the  ore  before  charging  dif- 
fers. Some  claim  that  for  good  practice  absolutely  dry  ore 
would  be  preferable,  while  others  consider  a  relatively  super- 
ficial drying  sufficient.  In  dry  climates  sun  dr>ing  ma}-  in 
cases  then  suffice.  In  many  furnace  plants  the  ore  is  dried  by 
spreading  over  iron  plates  on  the  top  of  the  first  condensers. 

In  other  plants,  for  instance  at  the  Oathill.  Great  Eastern,  etc., 
a   special  drier  is  used.     [See  Fig.  77.]     The  exhaust  steam 


Fig.  78.     Ore  drier.    Special  furnace  at  Abbott  Mine. 


15— QR 


228 


OUICKSILVliR    RESOURCES    OF    CALIFORNIA. 


from  the  engine  driving  the  fan  is  passed  through  coils  under 
the  platform  on  which  the  ore  is  spread.  At  the  same  time, 
at  Oathill,  exhaust  steam  is  brought  into  the  first  condenser. 
At  the  Abbott  mine,  a  special  furnace  is  used  to  heat  the  plat- 
form of  the  ore-drier.  [See  Fig.  78.]  Sixty  tons  of  ore  can 
be  dried  in  twenty-four  hours,  using  two  cords  of  oak  wood. 
The  ore  charged  in  furnace  No.  3,  at  New  Almaden,  passes 
through  a  brick  shell  surrounding  a  condenser,  and  provided 
with  a  series  of  tiles  placed  at  an  angle  of  45°,  thereby  obtain- 
ing the  double  result  of  drj'ing  the  damp  ore  and  materially 
increasing  the  condensation  in  the  condenser. 

Again  in  other  furnaces  the  ore  is  only  dried  while  in  the 

charging  hopper  and 
partly  in  the  upper  part 
of  the  furnace.  At  the 
Manhattan  furnace  a 
special  flue  conducts  the 
fumes  from  the  upper 
three  rows  of  tiles  to  the 
first  brick  condenser. 
These  fumes  are  prin- 
cipally water  vapor,  but 
yet  contain  some  mer- 
cur}'  vapors.  At  the 
New  Idria  furnace, 
where  the  fumes  ema- 
nating from  the  upper 
part  of  the  charge  are  highly  sulphuric,  due  to  a  great  amount 
of  iron  pyrites  in  the  ore,  the  device  indicated  in  Fig.  79  has 
been  adopted,  which  has  proven  ver}'  effective.  The  pipe  (e) 
goes  to  a  special  blower,  from  which  the  fumes  are  conveyed 
to  the  smokestack.  Mr.  Robert  Scott  proposed  to  dry  the  ore 
in  the  top  of  the  furnace  and  to  csLvry  off  the  fumes  there 
formed  by  making  the  tiles  of  the  upper  three  rows  of  cast- 
iron  and  hollow,  and  passing  the  fumes  through  these  hollow 
tiles,  instead  of  over  the  charge.  [See  Fig.  So.]  In  order  to 
prevent  the  clogging  at  the  top  of  the  furnace,  rakes  worked 
by  levers  from  the  charging  floor  are  used.      [See  Fig.  Si.] 

Mr.  H.  C.  Davey  divides  the  furnace  into  two  vertically  super- 
imposed compartments.  In  the  lower  part  the  roasting  takes 
place  as  in  the   Hiittner-Scott  furnace.      The  upper  part  is 


^y/J///h'//3y////^ 


—  <- 

Fig.  79.     New  Idria  fine-ore  furnace.     Method  of 
conveying  fumes  from  top. 

4 — Counterweight,  chained.  B — Furnace  hopper. 
C — Iron  door  D — Track  for  side  dumping  car. 
E — Cast  iron  pipe  (12'"  to  blower  and  smokestack. 


Fig.  So.     Top  of  the  modified  Scott  furnace.     Scale  %"-^i' 


232 


QUICKSILVER    RESOUKCES    OF    CALIFORNIA. 


heated,  by  a  separate  furnace,  only  to  the  temperature  required 
to  dry  the  ore.  The  ore  falls  through  a  narrow  vertical  throat 
from  the  upper  into  the  lower  compartment  of  the  furnace.     In 


the  modified  plan  of  Mr.  Scott,  above  mentioned,  this  end  is 
attained  bj'  bars  and  rakes.  [See  Fig.  So.]  To  cause  the  ore  to 
move  down  gradualh'  while  charging,  the  throat  below  the 
hopper  must  have  the  same  width  as  the  shelf- slit. 


234 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


The  discharging  of  the  furnace  is  also  done  in  various  ways. 
[See  the  detailed  plans  in  Egleston  and  Christy,  and  plans  in 
Figs.  73,  74,  and  82.]  Generally  the  hood  of  the  flue  carr^'ing 
off  the  fumes  emanating  while  discharging  is  close  to  the  tim- 
ber ib),  causing  danger  of  hot  dust  accumulating  against  the 
frame  timbers,  and  rendering  it  difficult  to  remove  the  dust. 
This  is  obviated  by  the  construction  shown  in  Fig.  83. 

The  general  arrangements  of 
furnace  plants  are  shown  in 
Fig.  84  (Oathill  furnace),  Fig. 
85  (Abbott  furnace),  and  Fig.  86 
(St.  John  furnace),  and  several 
photographs.  The  plan  of  the 
New  Almaden  is  given  on  a 
large  scale  in  the  works  of 
Egleston  and  Christy,  above 
cited.  Most  of  the  furnace 
plants  have  been  gradually  en- 
larged, and  as  their  site  is  nearly 
alwa^-s  in  a  mountainous  region, 
this  gradual  enlargement  has 
often  forced,  by  lack  of  proper 
room,  the  condensing  plant  to 
be  built  in  a  ver\-  irregular 
manner. 

The  condensing  of  the  fumes 
emanating  from  the  furnace  and  the  recovery  of  the  mercury 
offer  a  very  complicated  problem.  The  distillation  heat  of 
cinnabar  is  360°  C,  or  680°  F.,  hence  the  fumes  must  leave  the 
furnace  at  a  temperature  higher,  but  as  near  as  possible  to  it; 
the  theoretical  product  being  mercur}-  in  vapor  form  and 
sulphur  dioxide  (HgS^20  =  Hg+S0,). 

In  good  practice  the  temperatures  of  the  fumes  as  they  leave 
the  furnace  appear  to  come  very  near  to  this  limit.  [See 
Christy,  vol.  XIV,  above  cited,  page  226.] 


Fig.  S3.     New  Idria  fine-ore  furnace. 
Details  of  drawing  door. 

A — Sheet  iron  hood  carrying  away 
fumes.  B  —  Bracing  rod  and  hood 
(asbestos  covering).  C — Iron  door  in 
iron-lined  chute.    D — Ore  car. 


-xk  ^^0 

v^Nfj.!      i     i 

y 

^-^A. 


i>-^' 


f 

■  1^- 

i 

T 

I 


;Fi' 


i<  iiitiihjil  :ai-»nl  .'  '•.'sstnu)  bnr.  ?no9tti»baoo  io  noU'i-v 


Fig.  84. 


General  plan  of  reduction  works.    (Mineral  Industry.) 


Vertical  section  ol  condensers  and  furnace  on  A  B.    (Mineral  Industry.) 


furnace  and  elevation  showing  condensers.    (Mineral  Industry.) 


^^JK  »»»»'>\   ■^%»iWo'^ 


>^v>l4**') 


•-rf- 


IS 


♦.%M*VT 


A^-»\\vA->'\«>6 


'v<i.'-.>'Qt\»'b    ^wW  r'aV.qi^" 


^ 


^  TR 


wpyfc^w^*-^ 


J L__ JinjJ. 

^1  *^  *        V 


'1 

^. 

j           »»<VAU"\ 

i 

1 

5. 

a 

j',0 
^ 

> 

i^ 


(.-{i)Hnbu(  iBwniM)    .a^iow  noiioubsi  to  ujslq  IbtousO 


236 


QUICKSILVER    RESOURCES    OF    CALIFORNIA. 


Temperature  Determinations  as  Taken  by  Mr.  J.  R.  Smedberg, 
February,  iSSo,  with  Furnace  No.  9,  New  Almaden. 


Degrees 
Celsius. 

1.  Lowest  peep-hole  (above  fireplace) 823^ 

2.  Next  higher 946 

3.  Next  higher 878 

4.  Topmost  peep-hole  (near  furnace  throat) .  .  .  372 

5.  Entrance  to  first  brick  condenser* 190.6 

6.  End  of  second  brick  condenser 37.8 

7.  End  of  first  glass  and  wood  condenser 25.6 

S.  End  of  second  glass  and  wood  condenser.  . ;        17.8 
9.  End  of  third  glass  and  wood  condenser  ....       15.6 

10.  End  of  fourth  glass  and  wood  condenser.  .  .       14.4 

11.  End  of  fifth  glass  and  wood  condenser 14.4 

12.  End  of  sixth  glass  and  wood  condenser  ... .       13.9 

13.  End  of  wooden   flue,  entrance  to   sidehill 

flue 


Degrees 
Fahren- 
heit. 


1612 
701 

375 
100 
78 
64 
60 
5S 
58 
57 


Fall  in 
Degrees 
Celsius. 


iSi.r 

I52.S 
12.2 
7.8 
2.2 
1.2 
0.0 


O.: 


Fi&.  55.     sketch  showing  method  of  handling  ore  at  Abbott  Mine,  Lake  County. 


According  to  this  table,  the  cooling  takes  place  principally 
in  the  down-take  and  in  the  two  brick  condensers,  the  fumes 
being  cooled  to  a  temperature  of  37.S-  C,  and  moisture  begins 
already  to  appear.  It  is  to  be  regretted  that  the  results  of 
similar  temperature  determinations  on  a  modern  Hiittner- Scott 
plant  are  not  available. 

".After  passing  through  the  iron  down-take,  see  description  of  furnace. 


«^  — 


Co 

I 


u- 


- — i: 


— «» 


METALLURGY. 


239 


The  fumes  as  they  leave  the  furnace  are  far  from  resembling 
the  theoretical  product  of  distillation  of  mercuric  sulphide. 
These  are  mixed  with  the  roasting  products  of  the  ore,  to  wit: 
water  vapor,  carbon  dioxide,  and  mechanicalh'  entrained  ore 
dust;  and  the  products  of  combustion  of  the  fuel,  to  wit:  water 
vapor,  carbon  dioxide,  and  mechanically  entrained  ash.  In 
Volume  XIV  (above  cited),  page  234  and  following,  Professor 
Christy    gives   a   detailed   study   of   these    fumes    and    their 


PHOTO  Xo.  36.     GRE.A.T  EASTERX  FURNACES. 

behavior,  and  the  conditions  for  a  well-constructed  condensa- 
tion plant.  When  coming  in  contact  with  cool  surfaces,  the 
fumes  deposit  a  solid  material  known  as  "soot,"  consisting  of 
the  ore  dust,  ash,  some  tarry  hydrocarbons,  and  the  products  of 
the  decomposition  of  the  CO^  into  CO  and  O.  The  most 
important  condensed  constituents  are  water,  sulphates  of 
iron,  alkali  mercury,  and  sulphuric  acid.  The  water  absorbs 
from  the  condensed  vapors,  sulphurous  acid,  chloride  of 
ammonia,  hydrocarbons,  etc.  The  sulphuric  acid,  especially 
when  present  in  large  quantities,  as  in  the  case  when  roasting 


240 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


highl)^  pyritiferous  ores,  is  a  most  troublesome  product,  as  it 
attacks  every  material  out  of  which  condensers  are  constructed. 
The  soot  is  an  intermediate  product,  which  is  only  detrimental 
when  it  forms  in  excessive  quantities.  It  has  the  advantage 
of  retaining  the  minute  globules  of  mercurj^  which  form  at  the 
moment  of  sublimation  and  would  otherwise  be  carried  ofi  by 
the  gases.  [Mist  loss,  see  vol.  XIV,  above  cited,  page  233.] 
Spirek  [ly'Industria  del  Mercuria  in  Italia,  page  14]  mentions 
the  fact  that  the  soot  causes  the  mercury  contents  of  the 
fumes  to  be  below  the  saturation  point. 

The  products  of  the  condensers  are:  for  the  hot  condensers 
near  the  furnace,  mainly  dry  quicksilver  and  soot  mixed  with 
ore  dust;  farther  on,  quicksilver,  acid  water  (containing  mainly 
sulphuric  acid),  and  damp  soot;  for  the  last  condensers,  acid 
waters,  holding  various  sulphates  in  solution,  colored  black  by 
the  soot,  and  carrying  some  very  finely  divided  quicksilver; 


,(r 


'  Side£/er 


•lecond  Col/echha 
^U3^|      i  aunder 


Fig.  SS.    Installation  to  save  flour  mercury,  Xew  Almaden. 


finally,  for  the  flues  to  the  smokestack,  nearly  dry  soot  with 
very  little  quicksilver,  rarely  visible  to  the  naked  eye. 

The  quicksilver  is  collected  in  inclined  troughs  running 
along  the  outside  of  the  condensers.  [See  Fig.  87.]  The 
water  vapors  contain  some  very  finely  divided  mercury,  which 
floats  on  the  water  brought  down  by  their  condensation.  At 
New  Almaden,  a  special  installation  has  been  constructed  to 
save  this  quicksilver  [see  Fig.  88,  which  explains  itself],  and 
considerable  quicksilver  is  thus  secured.  Even  repeated  passage 
through  such  settling  boxes  will  not  save  all  the  minute 
quicksilver  globules. 

The  draft  in  the  fire  chamber  of  the  furnace  and  the  passage 
of  the  fumes  through  the  furnace  and  the  condensing  plant  to 
the  smokestack  are  caused  and  regulated  by  the  introduction 
of  a  blower  in  the  course  of  this  travel.  Sometimes  a  fire  draft 
at  or  near  the  stack  is  added,  and  at  the  Xew  Idria  furnace  an 


METALLURGY. 


243 


auxiliary  blower  is  used.  At  the  Abbott  furnace  the  blower 
is  placed  between  the  first  and  second  condensers — a  verj- 
unusual  location. 

The  condensing  plant,  as  above  stated,  must  answer  the 
double  purpose  of  cooling  the  fumes  and  causing  the  deposition 
of  the  liquefied  quicksilver.  Professor  Christ}'  [above  cited, 
vol.  KIV,  page  207]   concisely  states  the  various  difiiculties 


PHOTO  No.  JJ.     OCEANIC  QUICKSILVER  REDUCTIOX  PL.^NT,  SAN  LUIS 
OBISPO  COUNTY. 

encountered  in  this  operation,  as  follows:  "The  quicksilver 
"fumes  furnish  often  less  than  one  per  cent  by  volume  of  the 
"products  of  combustion  with  which  they  are  mixed." 

When  Professor  Christy  wrote  this  (1885),  the  mines  were 
running  on  much  higher  grade  ore  than  at  present;  0.5  per 
cent  is  a  fair  average  (even  probably  a  little  too  high)  of  the 
ore  now  passing  through  the  various  furnaces  in  the  State. 
The  volume  of  the  fumes  produced  is  [see  above  cited,  page 
236],  per  kilogram  of  ore,  0.185  cubic  meter,  at  o"  C.  and  760 
mm.  Hg:  that  of  the  vaporized  quicksilver 


244  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

I  cu.m.  >;   o.oos 

:^ — ^  =  0.00058  cu.  m., 

8.96  ^ 

or  0.31  per  cent  of  the  total  fumes. 

"Even  the  weight  of  the  quicksilver  is  inconsiderable  com- 
"  pared  with  that  of  the  gases  which  pass  through  the  con- 
"  denser." 

Under  the  present  conditions  as  above  mentioned  their  per- 
centage would  be: 

Hg  =0.005  kilogram. 
CO2  =  0.100         •' 
SO.  =  0.040 
N     =0.132         " 
Water  vapor  =  o.  100         " 

Total  weight  of  dr}-  gases 

at  0°  C.  and  760  mm.  Hg  =  o.377         " 
Weight  of  quicksilver  vapor 

at  0°  C.  and  760  mm.  Hg  =  0.005         "    or  1.3  per  cent  of  total  weight. 

Professor  Christy  continues:  "These  facts  add  greatly  to  the 
"difl5culties  of  condensation.  For  in  the  first  place,  the  heat 
"must  be  extracted  from  the  fumes  in  order  that  the  quick- 
"  silver  may  be  liquefied.  Next,  the  whole  volume  of  the  gases 
"must  pass  through  the  condensers  at  a  certain  velocity,  in 
"order  to  maintain  the  draft  of  the  furnace.  The  minute 
"condensed  globules  of  liquefied  quicksilver  are  likeh'  to  be 
"carried  oflf  in  the  form  of  'mist.'  The  gases  which  escape  from 
"the  condensing  S3'stem  are  necessaril}-  saturated  with  quick- 
"silver  vapor  at  the  temperature  of  escape."  (This  loss  is, 
however,  very  small.  Assuming,  as  Professor  Christy  does 
[page  245],  an  average  escape  temperature  of  20°  C,  the  cal- 
culated loss  would  be  0.83  per  cent  of  the  total  yield  [see 
Table  XIII,  page  243] ;  while  according  to  Mr.  Spirek  [see 
above,  page  i  S]  the  soot  prevents  the  fumes  from  being  satu- 
rated with  mercury  vapors.)  "  Then  there  is  the  ever-present 
"mercurial  soot,  which  requires  separate  treatment.  The 
"quicksilver  itself  is  read}-  to  escape  from  any  crack  or  crevice 
"of  the  condensers,  either  as  a  liquid  or  a  vapor.  Finally,  as 
"soon  as  the  condensers  become  cool  enough  to  act  effectively, 
"they  are  attacked  by  the  dilute  sulphuric  acid  formed  from 
"the  oxidation  of  the  sulphurous  acid  in  the  fumes.  This 
"agent  slowly  attacks  and  destroys  almost  ever\-  material  out 
"of  which  the  condensers  can  be  made." 

To  combine  the  effects  of  cooling  and  deposition  of  the  quick- 
silver in   the  most  preferable   manner,  three   factors  must  be 


PHOTO  No.  -JS.     INTERIOR  VIEW  OF  REDUCTION  WORKS, 
NEW  ALMADEN— HACIENDA. 


PHOT(J  No.  -1-1.     NEW  IDRIA,  SHOWING    ROUND   WOODEN    FLUE:  AND  WOODEN 
TANKS  USED  FOR  CONDENSERS. 


246 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


considered:  the  length  of  the  path  of  the  vapors  in  the  con- 
densing system,  the  interior  volume  of  the  system,  and  the  area 
of  the  cooling  surface.  It  is  to  be  regretted  that  very  little  data 
regarding  these  conditions  in  the  diflferent  furnace  plants  are 
available. 

Mr.  Robert  Scott  considers  the  condensing  room  required  for 
a  40-ton  furnace  17,000  cubic  feet,  and  for  a  50-ton  furnace, 
20,000  cubic  feet,  which  must  be  increased  as  the  ore  diminished 


PHOTO  No.  45.     RETORTING  SOOT,  GREAT  EASTERN  MINE. 

in  grade.  Professor  Christ}-  [above  cited,  page  224]  gives  this 
data  for  furnace  No.  i  at  New  Almaden.  The  totals  are:  Path 
of  vapors  from  furnace  to  top  of  chimney,  about  1000  feet; 
interior  volume,  26,667  cubic  feet;  cooling  area,  18,653  square 
feet;  ratio  of  cooling  area  to  interior  volume  is  0.69.  It  must 
be  remarked  that  the  brick  condensers  give  onl}-  a  ratio  of  0.5. 
In  the  brick  condensers  at  present  built  by  Robert  Scott,  the 
interior  volume  is  about  1927  cubic  feet;  the  cooling  area, 
922.5  square  feet;  giving  about  the  same  ratio. 

Following  is  a  table  furnished  by  Mr.  E.  W.  Carson,  super- 
intendent of  the  Oceanic  Quicksilver  Compam-: 


METALLURGY. 


247 


en  o 
V    u 

41 

0 

tj 

0 
■i-i 

6 

u 
3 
<n 

*5 
'S 

0 

u 

i. 

"  (0 

ii   n! 

if. 

tn 

45^ 

"o 

iiT 

^c« 

r^ 

X. 

'-   5? 

a 

^ 

y 

V- 

*^ 

o 

tj£           (U.«           1 

r^ 

0 

a 

f-^  (/} 

0 

■■^' "::; 

« 

13 
(U 
;-i 

> 

O 

o 

c 

o 
o 
tn 

1) 

s 

0 

O 
O 

41 

o  2 
a-  o 

41  tn 

41   3 
(J    41 

s 

a 

"c 

c 

OJ 

:>i 

^ 

5 

oJ 

4J 

3 

3  -^ 

r-" 

U 

•^ 

H 

Pi 

s 

£ 

'j5 

£Pa 

f2^ 

■vT 

M 

CO 

ts 

(N 

c 

'^      oo 

o 

CC 

•* 

>» 

(N 

ON           ON 

(N 

-*      -* 

VO 

(N 

•rt 

S-^^ 

<! 

ON 

^ 

ID 

t^        VO 

t^ 

"" 

ON 

•HfcS 

t. 

cr> 

lO 

cf; 

5  i.^ 

Lr, 

u  c 

bA 

^• 

r^ 

(S 

o 

0 

^■ 

o 

CO 

o 

CC 

ON 

oolinj 
Area. 

^ 

r^ 

rO 

VO 

CO 

lO          '^ 

^ 

cs 

-^ 

^ 

&• 

^c 

'OD 

^ 

t^ 

U 

0- 

^  (J 

^• 

\o 

p) 

CO 

0 

v£) 

to 

\o 

r* 

:>      >o 

•S  a 

V  3 

^ 

(N 

M 

rO 

tN 

to 

h^ 

\t 

^      ^ 

^ 

a> 

" 

CN 

C 

p) 

rO 

o_ 

SO 

a; 

M 

rO 

H-> 

^ 

**-  ,/ 

o!S 

£a 

"%! 

o 

o 

cs 

CC 

<N 

oo 

VO 

\c 

>.^ 

%J 

o 

HH 

F- 

r-        O 

On 

y~ 

ON 

ct  rt 

l*. 

ro 

(N 

•-H 

CO 

Ph> 

tc    . 

«   X 

11— ■ 

fi 

■$ 

X  ^ 

^ 

i; 

CO 

CO 

1- 

M 

t-< 

01 

cs 

'x'~ 

^ 

:-° 

1- 

^ 

J3 

a 

t^ 

vO 

(N 

<s 

-4- 

CO 

-I 

M 

M 

3 

iz; 

05 
l-c 

c/) 

•^-i 

4) 

0* 

<J 

en 

o; 

C 

ir. 

'C 

f2 

(U 

u 

.- 

X 

□ 

TJ 

v 

'u 

o 

a 

ndens 

fi 

■Ji 

u 

O 

o 

0 
0 

o 
u 

Ij 

^ 

0 

1       u 

t/5 

■X 

rt 

^ 

1- 

(J 

0. 

tr 

Oj 

0 

tn 

0) 

•^ 

X 

"3 

01 

lu 

\r 

■^ 

<u 

(/ 

O 

o 

U) 

in 

<u 

•■ 

"       t/i 

-*-» 

^ 

S 

C 

— 

C 

-1         OJ 

— 

1 

OJ 
3 
C3 

4» 

u 

4j 

OJ 

(U 

'^ 

;- 

<u 

c 

'^ 

"H 

_^ 

•s 

'w 

•r 

C 
0 
CJ 

c 

•X 

o 

5 

•^ 

o 

(U 

n 

J2 

— 

X 

y 

o 

/ 

0 

'J 

C 

H 

41 

41 

41 

CC 

^ 

^ 

0 

'c 

^ 

o 

O 

O 

o 

o 

CJ 

c 

*- 

Q 

1- 

o 

O 

O 

H 

'C 

n 

r 

u 

P5 

>• 

> 

> 

w 

fG 

— 

>— ' 

r-- 

f^ 

r* 

1 

METALLURGY. 


249 


The  ratio  of  the  cooling  area  and  interior  volume  is  here  for 
the  total  plant  H^  ol  =  0-39)  mainly  due  to  the  unscientific 
construction  of  the  brick  condensers  (built  before  Mr.  Carson 
arrived  on  the  property),  which  show  a  ratio  of  I'VrW  ^^^ 
f ^ff»  respectively  about  0.28  and  0.27.  Mr.  Carson  has  tried 
to  remedy  this  to  some  extent  b}-  cooling  the  top  of  the  first 
two  chambers  by  water.  In  fact,  this  plant  as  constructed  a 
few  years  ago  was  a  striking  example  of  the  result  when  met- 
allurgical work  is  placed  in  ignorant  hands. 


-z'C 


Fig.  90.     Knox  Ironclad  Condenser. 

A  great  number  of  different  condensers,  built  on  varying 
plans  and  with  varjdng  material,  have  been  devised.  Their 
details  can  be  found  in  the  works  above  cited.  At  present  the 
following  are  in  use  in  California: 

Brick  condensers  are  constructed  in  different  dimensions, 
from  9  by  5  feet,  5  feet  high  (the  small  brick  condensers  at  the 
Great  Western  mine  in  Lake  County),  to  8  by  16  feet,  29  feet 
high,  at  the  Oceanic.  The  condensers  at  present  built  by  Mr. 
Robert  Scott  are   14^4   by  8 '2    feet  inside,  22  feet  high  from 


Fig.  9! .    Water  Tank  Condenser. 


METALLURGY. 


251 


^^ 

i f 

1, 

! 

y       y 

lower  part  of  floor  to  top  of  building,  with  a  central  partition 
wall  to  deflect  the  fumes  on  their  passage,  an  inclined  bottom 
with  a  spring  of  15  inches,  and  earthenware  exit  pipes.  The 
side  walls  are  9  inches  thick.  They  are  generally  arch-topped, 
sometimes  covered  by  iron  plates.  [See  Fig.  89.]  Each  con- 
denser is  separated  from  the  one  adjoining  and  connected  by 
earthenware  pipes;  the  first  and  second  by  iron  flues. 

To  hasten  the  cooling  of  the  fumes,  narrow  iron  tanks  con- 
nected by  cast-iron  pipes  have  been  placed  in  some  plants, 
mainly  in  the  first  condenser  at  the  end  walls,  water  circulat- 
ing through  the  installa- 
tion, called  "waterbacks." 
[See  vol.  XIV,  page  216.] 
At  the  Karl  mine,  San 
Luis  Obispo  County, 
8-inch  tile  pipes,  through 
which  water  circulates, 
have  been  placed  in  the 
first  four  condensers. 

At  the  New  Idria  mine, 
stone  is'  used  for  the 
construction  of  some  con- 
densers. 

The  iron  condensers  at 
present  used  are  generally 
of  the  Knox  type.  [See 
Fig.  90,  and  Egleston, 
above  cited,  page  846.] 
Where  the  ore  does  not 
carry     too      much      iron 

sulphide,  they  stand  very  well.  At  the  Manhattan  mine,  on 
the  coarse-ore  furnace,  seven  iron  condensers  were  installed 
behind  two  brick-dust  chambers.  These  have  been  used  from 
1874  to  1877  and  from  1885  to  1887  continuously,  and  from 
1889  to  the  present  date  about  two  months  every  year.  All 
joints  are  luted  with  Portland  cement. 

Another  iron  condenser,  the  "water  tank  condenser"  [see 
Fig.  91],  is  used  at  New  Almaden  for  furnaces  Nos.  7,  8,  and  9. 
[See  Egleston,  page  860.]  These  condensers  give  very  good 
satisfaction. 


^Jte 


The  Baker  Flue. 


252 


QUICKSILVER    RESOURCES    OF   CALIFORNIA. 


The  farther  the  parts  of  the  condensing  plant  are  from  the 
furnace,  the  more  they  are  exposed  to  the  deteriorating  effects 
of  waters  carr^dng  sulphuric  acid,  and  experience  has  taught 
that  wood  is  the  onlj-  material  which  will  resist  the  eSects  to  a 
great  extent,  especially  pitch  pine,  hence  the  use  of  wooden 
constructions  in  those  parts  of  the  plants  which  are  not  exposed 
to  too  high  temperature.  At  New  Almaden  the  wooden  Baker 
& 


a" Tile  P/pa 


Q"TJIe  Pipe 


t  /// /  /// /  / //// /7Z 


£:jei/a  t/'on ,  ^sech'on . 

Fig.  93.     Wooden  Condenser  Box.  Corona  Mine. 

flue  [see  Fig.  92]  has  been  used  for  years.  Stave  pipe  flues  are 
now  frequently''  used  also  for  connections  between  brick  con- 
densers and  for  smokestacks.  Wooden  condensers  are  fre- 
quenth''  constructed,  especiall}-  in  the  form  of  barrels.  Those 
at  the  New  Idria  coarse-ore  furnace  have  a  diameter  of  8  feet 
and  are  14  feet  long.  Similar  wooden  barrel  condensers  are 
also  used  at  the  Karl  mine,  Oceanic  mine,  etc.  The  great 
difficulty  with  these  stave  constructions  lies  in  the  iron  bands, 
which  are  corroded,  especially  in  the  lower  half  of  the  circle, 


METAIXURGY, 


253 


which  at  the  New  Idria  have  been  replaced,  as  an  experiment 
by  wooden  bands  made  of  wheel  felloes. 

At  the  Corona  mine  a  wooden  box  has  been  erected  between 
the  fifth  brick  condenser  and  the  flue  to  smokestack.  This 
box  is  IOC  feet  long  and  traversed  by  8-inch  tile  pipes  for  air 


Fig.  94.    Soot-Cleaning  Machine. 

circulation,  in  order  to  cool  the  fumes.     [See  Fig.  93.]     The 
blower  is  between  the  fifth  condenser  and  this  box. 

In  the  smaller  mines  the  soot  is  still  worked  by  hand  as  de- 
scribed by  Egleston  [above  cited,  page  810,  and  vol.  XIV,  page 
230],  but  in  the  larger  mines,  soot  machines  are  used.  [See 
Fig.  94.]  Generally  the  residue  is  treated  in  retort  furnaces, 
but  at  New  Almaden  the  residue  is  re-charged  in  the  fine-ore 
furnace. 


ELEVATIONS. 


Elevations  for  which  no  authorities  are  given  are  from  barometrical  observations 
during  field  work  for  the  Quicksilver  Bulletin,  by  Wm.  Forstner,  Field  Assistant. 


COLUSA  COUNTY. 

Feet. 

Central  mine — Main  tunnel 1675 

Divide   between   Colusa  and  Lake  counties,  at  crossing  of  road 

from  Sulphur  Creek  to  Abbott  mine 2125 

Elgin  mine — Main  tunnel 2275 

Empire  mine — Tunnel  at  southeast  end 1715 

Tunnel  in  Sulphur  Creek 1475 

Manzanita  mine — Shaft 1950 

Sulphur  Creek — Blank  Springs  Hotel 1575 

Schoolhouse 1525 

Wide  Awake  mine — Office 1600 

EL  DORADO  COUNTY. 

Bernard  Quicksilver  mine — Tunnel 925 

Canon — Store 900 

Placer^-ille *i830 

FRESNO  COUNTY. 

Arambide  mine —  Tunnel 1440 

Corner  of  Fresno,  Kings,  and  Monterey  counties 3145 

Little  Panoche  Pass 1800 

Mexican  mine — Cabin 3640 

Providential  mine — Tunnel 1600 

Ridge  on  Gabilan  claim 2480 

KINGS  COUNTY. 

Avenal  Creek  at  mouth  of  Bull  Pen  Gulch 1530 

LAKE  COUNTY. 

Abbott  mine — Office 2000 

Shafthouse 2050 

Adams  Springs 2725 

Anderson  Springs 1475 

Baker  mine — Retort  furnace 1375 

Brown's  mill  on  Kelsey  Creek 1650 

*s   P.  R.  R.  Co. 

(254) 


ELEVATIONS.  255 

Feet. 

Bullion  mine — Collar  of  shaft 1540 

Chicago  mine — Cabin 2700 

Clear  Lake 1340,  +  1400,  i  1310 

Divide  between  Adobe  and  Kelsej'  creeks  near  Kelseyville 1725 

Divide  between  Lake  and  Sonoma  counties — 

Crossing  Great  Western  tollroad 2675 

Crossing  road  from  Helen  to  Bacon  mine 3210 

Pine  Mountain 3475 

Crossing  old  road  from  Middletown  to  Pine  Flat 3300 

Crossing  road  from  Middletown  to  Dewey's  mill 3200 

Mount  Cobb,  eastern  rim 4500 

Mount  Cobb,  northwest  point 4050 

Geyser  Rock,  northwest  of  Mount  Cobb 3660 

Glenbrook 2300 

Gordon  Springs 2500 

Great  Western  mine — Store 2080 

Helen  mine — Furnace 2760 

Howard  Springs 2180 

Jewess  mine — Cabin 2525 

Kelseyville 1435 

King  of  All  mine — Lower  tunnel    1875 

Lakeport 1400 

Lower  Lake 1400 

Lucitta  mine — Retort  furnace I975 

Middletown    1200 

Middletown  mine — Upper  works    2400 

Mirabel — Office  Standard  Quicksilver  Co. 1460 

Mount  McGuire 2750 

Red  Elephant  mine — Cabin 1S25 

Road  from  Lower  Lake  to  Abbott  mine- 
Forks  of  Bartlett  Springs  and  Abbott  roads 1415 

Divide  at  head  of  Phipps  Creek 1570 

Crossing  Cache  Creek 1050 

Road  from  Lower  Lake  to  Knoxville — 

Crossing  branch  of  Soda  Creek  at  Baker  mine 1315 

Morgan  Valley  schoolhouse 2475 

Road  from  Middletown  to  Glenbrook  — 

Divide  between  Putah  and  Keisey  creeks 2650 

Road  from  Middletown  to  Oathili — 

Bridge  over  Bucksnorter  Creek 1190 

Sulphur  Bank  mine — Office 1450 

Collar  of  Diamond  shaft   1345 

Collar  of  Empire  shaft 1345 

Collar  of  Herman  shaft 1365 

Wagon  Spring  cut,  bottom 1390 

Western  cut,  bottom   1325 

Thorn  mine — Tunnel 2040 

t  Treadwell.     J  Clear  Lake  Water  Co. 


256  QUICKSILVER    RESOURCES    OF    CALIFORNIA. 

MERCED  COUNTY. 

Feet. 

Cathedral  Peak 3450 

Saddle  between  Cathedral  Peak  and  Mariposa  Peak   2850 

Stayton  mine — Cabin 2880 

Old  furnace  (Gj^psy) 2400 

MONTEREY  COUNTY. 

Cholame  and  Parkfield  mine — Top  of  ridge 3460 

Dutro  mine,  at  head  of  west  fork  of  San  Carpojo  Creek 1630 

Parkfield 1540 

Table  Mountain — Top  of  ridge 3300 

Table  Mountain  Quicksilver  mine — Cabin 3190 

NAPA  COUNTY. 

^tna  mine — Basalt  ridge,  Silver  Bow  claim 2050 

Office  and  Tunnel  No.  7 1240 

Tunnel  No.  5 1400 

Tunnel  No.  2  1600 

^tna  Springs 800 

Boston  mine  (Knoxville) — Office 1275 

Calistoga *363 

Corona  mine — Boiler  house  and  tunnel i960 

Manhattan  mine  (Knoxville) — Office 1925 

Oathill  mine — Office 2025 

Philadelphia  mine — Works  on  ridge 2040 

Road  from  Calistoga  to  ^ijtna  Springs — 

Summit  of  Howell  Mountain 2250 

Flat  between  Twin  Peaks 2440 

Forks  of  road  to  Oathill 2160 

Road  from  Middletown  to  Calistoga — 

Toll  house  at  Mount  St.  Helena 2300 

SAN  BENITO  COUNTY. 

Antimony  Peak,  Stayton  District 3150 

Aurora    mine — Furnace 3S25 

Bradford  mine  (Cerro  Gordol — Office 1820 

Cannon  mine — Tunnel 1560 

Cerro  Bouito  mine — Main  tunnel 2775 

Office 2440 

Top  of  Cerro  Bonito  hill 3250 

Clear  Creek  mine — Old  Monterey  furnace 2800 

Lower  workings 311° 

Upper  workings    3660 

Divide  between  San  Carlos  and  Clear  Creek,  crossing  of  road  from 

New  Idria  to  Hernandez 44J^o 

*S.  P.  R.  R.  Co. 


ELEVATIONS.  257 

Feet. 

Dominic  Peak 4720 

Don  Juan  mine — Old  furnace   2785 

Elkhorn 1 100 

Emmett  schoolhouse   1140 

Henrietta  Peak,  Stayton  District   3480 

Hernandez  P.  0 2540 

Hollister *286 

Llanada  P.  O.,  Panoche  Valley 1540 

Los  Picaclios  mine  (Ramirez  Cons.) — Retort  furnace 4600 

Mariposa  mine,  Staj-ton  District — Old  works 2700 

Mariposa  Peak 334o 

Mount  Venado 4660 

New  Idria  mine — Croppings  on  top  of  hill 375o 

Furnaces 2720 

Mine  boarding-house 334o 

North  Idria  Peak,  knoll  above  furnaces 3640 

North  San  Carlos  Peak 4660 

Office 2590 

San  Carlos  mine  tunnel 4500 

San  Carlos  Peak 4980 

Upper  fall,  San  Carlos  creek 3720 

Panoche  divide 2240 

Panoche  P.  0 1250 

Park  Mills 1440 

San  Benito 1540 

Shiver  mine,  Stayton  District 2460 

Tres  Pinos *5 1 2 

SAN  LUIS  OBISPO  COUNTY. 

Alice  and  Modoc  mine — Retort  furnace 1900 

Bank  mine — Main  tunnel 345 

Cambria 60 

Cholame  P.  O 670 

Cypress  Mountain  mine — Cabin 2425 

Cypress  Mountain — Plateau 2900 

Divide  between  Hughes  and  Santa  Rosa  Creek  on  road  to  Cambria .  2350 
Divide  between  San  Luis  Obispo  and  Santa  Margarita,  on  wagon 

road 1550 

Doty  mine — Lower  tunnel 2000 

Elizabeth  mine — Retort  furnace 1950 

El  Paso  de  Robles *  722 

Exline  mine — Tunnel loio 

Karl  mine — Furnace 1080 

La  Libertad  mine — Retort  furnace iSoo 

Lehman  mine   1975 

Madrone  mine — Retort  furnace   1950 

*s.  P.  R.  R.  Co. 


258  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

Feet. 

Mahoney  mine — Retort  furnace 1140 

Oceanic  mine — Furnace 400 

Main  tunnel   770 

Oceanic  mine  No.  2 1575 

Pine  Mountain — North  end  of  ridge 3125 

Top  of  ridge +  3560 

Pine  Mountain  mine — Ocean  View  tunnel 2815 

Office 2940 

Sawmill 3010 

Polar  Star  mine — Cabin 200 

Rinconada  mine — Croppings 2040 

Furnace 1750 

Rocky  Buttes -j-  3444 

Ouien  Sabe  mine — Lower  tunnel 1945 

San  Luis  Obispo *  23S 

Santa  Margarita *  996 

Vulture  mine 1460 

SANTA  CLARA  COUNTY. 

Bernal  mine — Works  on  ridge 650 

Comstock  mine,  Stayton  District — Furnace 1400 

Costello  mine — Main  tunnel 1000 

Guadalupe  mine — Furnace 340 

Guadalupe  schoolhouse 290 

Hillsdale  mine — Old  furnace    120 

New  Almaden  mine — America  shaft 1560 

Mine  Hill  top .  1600 

Randol  shaft    1220 

Office 1335 

R.  R.  B.  shaft,  Enriquita 950 

San  Jose 60 

Santa  Teresa  mine — Office 26c 

STANISLAUS  COUNTY. 

Adobe  mine — Collar  of  shaft   1900 

Orestimba  mine 2250 

Summit  mine — Office 2250 

SONOMA  COUNTY. 

Bacon  Consolidated  mine  iPine  Mountain) — Old  furnace  site 2900 

Boston  mine  (Pine  Flat) — Cabin 2525 

Cinnabar  King  mine — Cabin 2900 


*s.  P   R.  R.Co. 

t  U.  S.  Coast  aud  Geodetic  Survej-. 


APPENDIX 


17— QR 


CALIFORNIA  STATE  MINING  BUREAU. 


This  institution  aims  to  be  the  chief  source  of  reliable 
information  about  the  mineral  resources  and  mining  indus- 
tries of  California. 

It  is  encouraged  in  its  work  by  the  fact  that  its  publications 
have  been  in  such  demand  that  large  editions  are  soon  ex- 
hausted. In  fact,  copies  of  them  now  command  high  prices  in 
the  market. 

The  publications,  as  soon  as  issued,  find  their  way  to  the 
scientific,  public,  and  private  libraries  of  all  countries. 

STATE   MINERALOGIST. 

The  California  State  Mining  Bureau  is  under  the  supervision 
of  Hon.  Lewis  E.  Aubury,  State  Mineralogist. 

It  is  supported  by  legislative  appropriations,  and  in  some 
degree  performs  work  similar  to  that  of  the  geological  surveys 
of  other  states;  but  its  purposes  and  functions  are  mainly 
practical,  the  scientific  work  being  clearly  subordinate  to  the 
economic  phases  of  the  mineral  field,  as  shown  by  the  organic 
law  governing  the  Bureau,  which  is  as  follows: 

Sec  4.  It  shall  be  the  duty  of  said  State  Mineralogist  to  make, 
facilitate,  and  encourage  special  studies  of  the  mineral  resources  and 
mineral  industries  of  the  State.  It  shall  be  his  duty:  To  collect  statistics 
concerning  the  occurrence  of  the  economically  important  minerals  and 
the  methods  pursued  in  making  their  valuable  constituents  available  for 
commercial  use;  to  make  a  collection  of  typical  geological  and  miner- 
alogical  specimens,  especially  those  of  economic  or  commercial  impor- 
tance, such  collection  constituting  the  Museum  of  the  State  Mining 
Bureau;  to  provide  a  library  of  books,  reports,  drawings,  bearing  upon 
the  mineral  industries,  the  sciences  of  mineralogy  and  geology  and  the 
arts  of  mining  and  metallurgy,  such  library  constituting  the  Library 
of  the  State  Mining  Bureau;  to  make  a  collection  of  models,  drawings, 
and  descriptions  of  the  mechanical  appliances  used  in  mining  and 
metallurgical  processes;  to  preserve  and  so  maintain  such  collections  and 
library  as  to  make  them  available  for  reference  and  examination,  and 
open  to  public  ihspection  at  reasonable  hours;  to  maintain,  in  effect,  a 
bureau  of  information  concerning  the  mineral  industries  of  this  State,  to 
consist  of  such  collections  and  library,  and  to  arrange,  classify,  catalogue, 
and  index  the  data  therein  contained,  in  a  manner  to  make  the  informa- 
tion available  to  those  desiring  it,  and  to  provide  a  custodian  specially 


APPENDIX.  263 

qualified  to  promote  this  purpose;  to  make  a  biennial  report  to  the 
Board  of  Trustees  of  the  Mining  Bureau,  setting  forth  the  important 
results  of  his  work,  and  to  issue  from  time  to  time  such  bulletins  as  he 
may  deem  advisable  concerning  the  statistics  and  technology  of  the 
mineral  industries  of  this  State. 

THE  BULLETINS. 

The  field  covered  by  the  books  issued   under   this    title  is 

shown  in  the  list  of  publications.     Each  bulletin   deals  with 

only   one   phase   of    mining.     Many   of    them   are   elaborately 

illustrated  with  engravings  and  maps.     Only  a  nominal  price 

is  asked,  in  order  that  those  who  need  them  most  may  obtain 

a  copv. 

THE  REGISTERS  OF  MINES. 

The  Registers  of  Mines  form  practically  both  a  State  and 
County  directory  of  the  mines  of  California,  each  county  being 
represented  in  a  separate  pamphlet.  Those  who  wish  to  learn 
the  essential  facts  about  any  particular  mine  are  referred  to 
them.  The  facts  and  figures  are  given  in  tabular  form,  and 
are  accompanied  b}'  a  topographical  map  of  the  county  on  a 
large  scale,  showing  location  of  each  mineral  deposit,  towns, 
railroads,  roads,  power  lines,  ditches,  etc. 

HOME  OF  THE  BUREAU. 

The  Mining  Bureau  occupies  the  north  half  of  the  third  floor 
of  the  Ferry  Building,  in  San  Francisco.  All  visitors  and  resi- 
dents are  invited  to  inspect  the  Museum  Librar}',  and  other 
rooms  of  the  Bureau   and   gain   a  personal  knowledge   of  its 

operations. 

THE  MUSEUM. 

The  Museum  now  contains  over  16,000  specimens,  carefully 
labeled  and  attractively  arranged  in  showcases  in  a  great,  well- 
lighted  hall,  where  they  can  be  easily  studied.  The  collection 
of  ores  from  California  mines  is  of  course  very  extensive,  and 
is  supplemented  by  many  cases  of  characteristic  ores  from  the 
principal  mining  districts  of  the  world.  The  educational  value 
of  the  exhibit  is  constantly  increased  by  substituting  the  best 
specimens  obtainable  for  those  of  less  value. 

These  mineral  collections  are  not  only  interesting,  beautiful, 
and  in  every  way  attractive  to  the  sightseers  of  all  classes,  but 
are  also  educational.  They  show  to  manufacturers,  miners, 
capitalists,  and  others  the  character  and  quality  of  .the  economic 


264  QUICKSILVER    RESOURCES   OF   CALIFORNIA. 

minerals  of  the  State,  and  where  the}'  are  found.  Plans  have 
been  formulated  to  extend  the  usefulness  of  the  exhibit  by 
special  collections,  such  as  one  showing  the  chemical  com- 
position of  minerals;  another  showing  the  mineralogical 
composition  of  the  sedimentar}-,  metamorphic,  and  igneous 
rocks  of  the  State:  the  petroleum-bearing  formations,  ore 
bodies,  and  their  country  rocks,  etc. 

Besides  the  mineral  specimens,  there  are  many  models,  maps, 
photographs,  and  diagrams  illustrating  the  modern  practice  of 
mining,  milling,  and  concentrating,  and  the  technology  of  the 
mineral  industries.  An  educational  series  of  specimens  for 
high  schools  has  been  inaugurated,  and  new  plans  are  being 
formulated  that  will  make  the  Museum  even  more  useful  in  the 
future  than  in  the  past.  Its  popularity  is  shown  by  the  fact 
that  over  100,000  visitors  registered  last  year,  while  many 
failed  to  leave  any  record  of  their  visit. 

THE  LIBRARY. 

This  is  the  mining  reference  library  of  the  State,  constantly' 
consulted  by  mining  men.  and  contains  between  4,000  and 
5.000  volumes  of  selected  works,  in  addition  to  the  numerous 
publications  of  the  Bureau  itself.  On  its  shelves  will  be  found 
reports  on  geology,  mineralogy,  mining,  etc.,  published  by 
states,  governments,  and  individuals;  the  reports  of  scientific 
societies  at  home  and  abroad;  encyclopaedias,  scientific  papers, 
and  magazines;  mining  publications;  and  the  current  litera- 
ture of  mining  ever  needed  in  a  reference  libran,'. 

Manufacturers'  catalogues  of  mining  and  milling  machinery 
by  California  firms  are  kept  on  file.  The  Registers  of  Mines 
form  an  up-to-date  director}'  for  investor  and  manufacturer. 

The  librarian's  desk  is  the  general  bureau  of  information, 
w^here  visitors  from  all  parts  of  the  world  are  ever  seeking 
information  about  all  parts  of  California. 

READING-ROOM. 

This  is  a  part  of  the  Library  Department  and  is  supplied 
with  over  one  hundred  current  publications.  A'isitors  will  find 
here  various  California  papers  and  leading  mining  journals 
from  all  over  the  world. 

The  Library  and  Reading-Room  are  open  to  the  public  from 
9  A.  M.  to  5  p.  M.  daih',  except  Sundays  and  holidays,  and  from 
9  A.  M.  to  12  M.  on  Saturday's. 


APPENDIX.  265 

THE  LABORATORY. 

This  department  identifies  for  the  prospector  the  minerals  he 
finds,  and  tells  him  the  nature  of  the  wall  rocks  or  dykes  he 
may  encounter  in  his  workings;  but  this  department  does  not 
do  assaying  nor  compete  with  private  assa3'ers.  The  presence 
of  minerals  is  determined,  but  not  the  percentage  present.  Xo 
charges  for  this  service  are  made  to  any  resident  of  the  State. 
Many  of  the  inquiries  made  of  this  department  have  brought 
capital  to  the  development  of  new  districts.  Many  technical 
questions  have  been  asked  and  answered  as  to  the  best  chemi- 
cal and  mechanical  processes  of  handling  ores  and  raw  mate- 
rial.    The  laboratory  is  well  equipped. 

THE  DRAUGHTING-ROOM. 

In  this  room  are  prepared  scores  of  maps,  from  the  small 
ones  filling  only  a  part  of  a  page,  to  the  largest  County  and 
State  maps;  and  the  numerous  illustrations,  other  than  photo- 
graphs, that  are  constantly  being  required  for  the  Bulletins 
and  Registers  of  Mines.  In  this  room,  also,  will  be  found  a 
ver}-  complete  collection  of  maps  of  all  kinds  relating  to  the 
industries  of  the  State,  and  one  of  the  important  duties  of  the 
department  is  to  make  such  additions  and  corrections  as  wijl 
keep  the  maps  up  to  date.  The  seeker  after  information 
inquires  here  if  he  wishes  to  know  about  the  geology  or  topog- 
raphy of  an}'  district;  about  the  locations  of  the  new  camps, 
or  positions  of  old  or  abandoned  ones;  about  railroads,  stage 
roads,  and  trails;  or  about  the  working  drawings  of  anything 
connected  with  mining. 

MINERAL  STATISTICS. 

One  of  the  features  of  this  institution  is  its  mineral  statis- 
tics. Their  annual  compilation  by  the  State  Mining  Bureau 
began  in  1893.  Xo  other  State  in  the  Union  attempts  so  elab- 
orate a  record,  expends  so  much  labor  and  monej-  on  its  com- 
pilation, or  secures  so  accurate  a  one. 

The  State  Mining  Bureau  keeps  a  careful,  up-to-date,  and 
reliable  but  confidential  register  of  every  producing  mine, 
mine-owner,  and  mineral  industry  in  the  State.  From  them 
are  secured,  under  pledge  of  secrec)',  reports  of  output,  etc., 


266 


QUICKSILVER    RESOURCES   OF   CALIFORNIA. 


and  all  other  available  sources  of  information  are  used  in 
checking,  verifying,  and  supplementing  the  information  so 
gained.  This  information  is  published  in  an  annual  tabulated, 
statistical,  single-sheet  bulletin,  showing  the  mineral  produc- 
tion by  both  substances  and  counties. 

TOTAL  GOLD  PRODUCT  OF  CALIFORNIA— 1848  1906. 


1S48 $245,301 

1849 .  10,151,360 

1850 41,273,106 

1851 75-938.232 

1852 81,294,700 

1853 67,613,487 

1854  - 69,433,931 

1855- 55485.395 

1856 _  57,509,411 

1857 43,628,172 

1858  46.591.140 

1859 --  45.846.599 

i860  44,095,163 

1861 41,884.995 

1862 38,854,668 

1863 23,501,736 


864  $24,071,423 

865 17.930.858 

866  17,123,867 

867 18,265,452 

868 17.555.867 

869  18,229.044 

870 17.458,133 

871 17.477.885 

872 15,482,194 

873 15.019,210 

874 17,264,836 

16,876,009 

876 15,610,723 

877 16,501,268 

878 18,839.141 

879 19,626,654  , 


880  _ $20,030,761 

881 19,223,155 

882  17,146,416 

883 24,316,873 

884 13,600,000 

885  12,661,044 

886 14,716,506 

887 13,588,614 

888 12,750,000 

889 11,212,913 

890 12,309,793 

891 12.728,869 

892       ...  12,571,900 

893 12,422,811 

894 13,923,281 

895 -  15.334.317 


1896 _  $17,181,562 

1897..   -     .  15,871,401 

1898 15,906,478 

1899  -  15.336.031 

1900  15.863,355 

1901 16,989.044 

1902  16.910.320 

1903 16,471,264 

1904.. 19.109,600 

1905..  19.197.043 

1906 18,732,452 

Total..  _  1,452,785,763 


TOTAL  QUICKSILVER  PRODUCT  OF  CALIFORNIA— 1887-1906. 


Flasks. 

1887 33,760 

1888 33.250 

1889 26,464 

1890    22,926 

1891    22,904 

1892 27,993 

1893    30,164 

1S94    30,416 

1895 36,104 

1896 30,765 

1897 26,648 

1898 31,092 


Value. 
51,425,000 
1,413.125 
1,190,500 
1,203.615 
1,036,386 
1,139,600 
1,108,527 

934,000 
1,337,131 
I. .075, 449 

993,445 
1,188,626 


Flasks. 

1899 29,454 

1900 26,317 

190I 26,720 

1902    29,552 

1903 32,094 

1904 28,876 

1905    24,655 

1906 19,516 

Total  for  20 

years     ...  569,670 


51,405,045 
1,182,786 
1,285,014 
1.276,524 
1,3.^5,954 
1,086,323 
886, 08 1 
712,334 


523,215,465 


APPENDIX. 


267 


MINERAL  PRODUCTS  OF  CALIFORNIA  FOR  1906. 

The  yield  and  value  of  the  mineral  substances  of  California 
for  1906  was  as  follows,  as  per  returns  received  at  the  State 
Mining  Bureau,  San  Francisco,  in  answer  to  inquiries  sent  to 
producers: 


Asbestos Tons 

Asphalt Tons 

Bituminous  Rock  .  .Tons 

Borax  (Crude)    ....   Tons 

Cement Bbls 

Chrome Tons 

Clays  (Brick) M 

Clays  (Pottery)  .  .  .  .Tons 

Coal ;  Tons 

Copper Lbs 

Fullers'  Earth Tons 

Gems 

Glass  Sand Tons 

Gold     

Granite Cu.  ft 

Infusorial  Earth   .  .  .  Tons 

Gypsum Tons 

Lead Lbs 

Lime Bbls 

Limestone Tons 

Macadam      . .    Tons 

Manganese     Tons 

Magnesite  (Crude)    Tons 

Marble Cu.  ft 

Mineral  Paint Tons 

Mineral  Water Gals 

Natural  Gas M.  Cu.  ft 

Paving  Blocks M 

Petroleum Bbls 

Platinum Ounces  

Pyrites Tons .    

Quicksilver P'lasks 

Rubble Tons 

Salt Tons 

Sandstone Cu.  ft 

Serpentine Cu.  ft 

Soda Tons 

Silver (Commercial  Value) 

Slate Squares 

Tungsten 

Zinc Lbs 


70 

77,756 

16,077 

58,173   I 

1,286,000 I 

317 

277,762 2 

167,267 

24,850 

28,726,448 5 

440  


9,750. 


329,810. 

2,430- 

21,000. 

338,718. 

689,268 

80,262 

1,066,164. 

I 

4,032 

31,400. 

250. 

1,585,690. 

168,175. 

4,203. 

32,624,000. 

91.46. 

46,689 

19,516 

489, 208 . 

101,650. 

182,076. 

847. 
12,000. 


10,000. 
206,000. 


$3,500 
777,560 

45,204 
182,410 
.941,250 
2.859 
538,848 
162,283 

6r,6oo 
522,712 

10,500 
497,090 

13,375 
.732,452 
344,083 

14,400 

69,000 

19,307 

763,060 

162,827 

870,887 

30 

40,320 

75,800 

1,720 

478,186 

109,489 

173,432 
238,020 
1,647 
145,895 
712,334 
547,519 
213,228 
164,068 
1,694 

18,000 
817,830 
100,000 
189,100 

12,566 


Totals $46, 776,085 

Quicksilver  was  produced  in  Lake,  Napa,  San  Benito,  San  Luis 
Obispo,  Santa  Clara,  Solano,  Sonoma  and  Trinity  counties. 


268  OnCKSILVER    resources   of    CALIFORNIA. 


MINING  BUREAU  PUBLICATIONS. 

Publications  of  this  Bureau  will  be  sent  on  receipt  of  the 
requisite  amount  and  postage.  Only  stajnps,  coin  or  money 
orders  will  be  accepted  in  payment.  Do  not  send  personal 
checks. 

Address  all  communications  regarding  publications  to 
Librarian. 

(All  publications  not  mentioned  are  exhausted.) 

SALE  OF  MINING  BUREAU  PUBLICATIONS. 

Under  Section  8,  amendment  to  the  Mining  Bureau  Act, 
approved  March  lo,  1903,  your  attention  is  respectfully  called 
to  that  portion  of  the  amendment  which  states: 

"The  Board  (Board  of  Trustees)  is  hereby  empowered  to  fix 
a  price  upon,  and  to  dispose  of  to  the  public,  at  such  prices, 
any  and  all  publications  of  the  Bureau,  including  reports, 
bulletins,  maps,  registers,  etc.  The  sum  derived  from  such 
disposition  must  be  accounted  for  and  used  as  a  revolving 
printing  and  publishing  fund  for  other  reports,  bulletins,  maps, 
registers,  etc.  The  prices  fixed  must  approximate  the  actual 
cost  of  printing  and  issuing  the  respective  reports,  bulletins, 
maps,  registers,  etc.,  without  reference  to  the  cost  of  obtaining 
and  preparing  the  information  embraced  therein." 

Report     XI — 1S92,  First  Biennial  - .- — $i.oo 

Report  XIII— 1S95,  Third  Biennial.-' .  .-   

Bulletin  Xo.    6 — '•Gold  Mill  Practices  in  California"  (3d  edition)    

Bulletin  No.    9 — •Mine  Drainage.  Pumps.  Etc  "     Bound    -. 

Bulletin  Xo.  15— "Map  of  Oil  City  Oil  Fields,  Fresno  County,  California" 

Bulletin  No.  23 — 'Copper  Resources  of  California"      _     _-.       

Bulletin  No   24— "Saline  Deposits  of  California" _ 50 

Bulletin  No.  27— "Quicksilver  Resources  of  California"- .       .75 

Bulletin  No.  30— 'Bibliography-   Relating  to  the   Geolog>-,   Palaeontology 

and  Mineral  Resources  of  California,"  including  list  of  maps .50 

Bulletin  No.  31 — "Chemical  Analysis  of  California  Petroleum" - 

Bulletin  Xo.  32— "Production  and  Use  of  California  Petroleum"  - 

Bulletin  Xo.  36 — "Gold  Dredging  in  California  "     (2d  edition) 

Bulletin  Xo.  37-  "Gems  and  Jewelers'  Materials  of  California."     (2d  ed.) 

Bulletin  Xo.  3S— "Structural  and  Industrial  Materials  of  California" 

Bulletin  Xo.  42 — "Mineral  Production  of  California" — 1905 

Bulletin  Xo.  43— "Mineral  Production  of  California  for  Xineteen  Vears"- 

BuUetin  Xo  45 — ".Auriferous  Black  Sands  of  California"    ... 

Bulletin  Xo.  46 — ''Index  of  Mining  Bureau  Publications  '   .- ... 

Bulletin  Xo.  47— "Mineral  Production  of  California"— 1906 

Bulletin  Xo.  4S— "Mineral  Production  of  California  for  Twenty  Years"-.. 

Bulletin  Xo.  49— "Mines  and  Minerals  of  California" - 

California  Mine  Bell  Signals  (Cardboard) - 

California  Mine  Bell  Signals  (Paper) 

Gold  Production  in  California  from  184S  to  1906    

Register  of  Mines,  with  Map,  .\mador  County 

Register  of  Mines,  with  Map,  Butte  County   -.. 

Register  of  Mines,  with  Map.  El  Dorado  County 

Register  of  Mines,  with  Map.  Inyo  County -  -. 

Register  of  Mines,  with  Map,  Kern  County 25 

Register  of  Mines,  with  Map,  Lake  County 


Post- 

rice. 

Il.OO 

1. 00 

age. 

$0.15 
.20 

•50 
.60 

.04 
.oS 

■05 
•50 

.02 

.12 

■75 

.08 

■50 

.oS 

■50 

.oS 

•75 

.20 

.02 

.02 

.10 

.02 

•30 

.06 

02 

... 

.02 

•05 

.02 

•03 

.02 

.02 

•25 

.oS 

■25 

.oS 

■25 

.oS 

■25 

.oS 

•25 

.08 

•25 

.OS 

APPENDIX.  269 

Post- 
Price,       age. 

Register  of  Mines,  with  Map,  Mariposa  Couuty $0.25        $0.08 

Register  of  Mines,  with  Map,  Nevada  County  ...   .25 

Register  of  Mines,  with  Map,  Placer  County .25 

Register  of  Mines,  with  Map,  San  Bernardino  Countj' .25 

Register  of  Mines,  with  Map,  San  Diego  County 1 25  .08 

Register  of  Mines,  with  Map.  Santa  Barbara  County 25 

Register  ot  Mines,  with  Map.  Shasta  County  25  .08 

Register  of  Mines,  with  JIap.  Sierra  County _ 25 

Register  of  Mines,  with  Map,  Siskiyou  County .25 

Register  of  Mines,  with  Map,  Trinity  County 25 

Register  of  Mines,  with  Map,  Tuolumne  Countj- .   25 

Register  of  Mines,  with  Map.  Yuba  County  .....   __.   .25 

Register  of  Oil  Wells,  with  Map,  t,os  Angeles  City .35 

Map  of  Mother  Lode   .     . .05 

Jlap  of  Desert  Region  of  California _ • 10 

!Map  Showing  Copper  Deposits  in  California ._ 05 

Map  of  Calaveras  County  .._ .25  .03 

Map  of  Plumas  County .25  .03 

Mineral  and  Relief  Map  of  California .25  .05 

Map  of  Forest  Reserves  in  California  (Mounted). 50 

Map  of  Forest  Reserves  in  California  (Unmounted) .30 

In  Preparation — 
Map  and  Register  of  Madera  County. 
Report  on  Minaret  District. 
Bulletin — "Revised  Edition  Copper  Resources  of  California." 

Samples  (limited  to  three  at  one  time)  of  any  mineral  found 
in  the  State  ma}-  be  sent  to  the  Bureau  for  identification,  and 
the  same  will  be  classified  free  of  charge.  /Vo  samples  will  be 
determined  if  received  from  points  outside  the  State.  It  must 
be  understood  that  no  Assays  or  Quantitative  Determinations 
zvill  be  made.  Samples  should  be  in  a  lump  form  if  possible, 
and  tnarked plainly  with  name  of  sender  outside  of  package, 
postoffice  address.,  etc.  No  sajnples  will  be  received  unless 
charges  are  prepaid.  A  letter  should  accompanj-  sample  and 
a  stamp  should  be  enclosed  for  repl)-. 

Address  all  samples  and  communications  regarding  samples 
to  Laboratory. 

LAW  RELATING  TO  MISREPRESENTATION  OF  MINES  BY  ANY 
OFFICER  OF  A  CORPORATION  TRANSACTING  BUSINESS  IN 
CALIFORNIA. 

Section  i.  Anj^superintendent,  director,  secretary,  manager, 
agent,  or  other  officer,  of  any  corporation  formed  or  existing 
under  the  laws  of  this  State,  or  transacting  business  in  the 
same,  and  any  person  pretending  or  holding  him.self  out  as 
such  superintendent,  director,  secretary,  manager,  agent  or 
other  officer,  who  shall  willfully  subscribe,  sign,  endorse,  verify, 
or  otherwise  assent  to  the  publication,  either  generally  or 
privately,  to  the  stockholders  or  other  persons  dealing  with 
such  corporation  or  its  stock,  any  untrue  or  willfully  and 
fraudulently  exaggerated  report,  prospectus,  account,  statement 


270  QUICKSILVER    RESOURCES   OF    CALIFORNIA. 

of  operations,  values,  business,  profits,  expenditures  or  pros- 
pects, or  other  paper  or  document  intended  to  produce  or  give, 
or  having  a  tendency  to  produce  or  give,  to  the  shares  of  stock 
in  such  corporation  a  greater  value  or  less  apparent  or  market 
value  than  they  really  possess,  or  with  the  intention  of  defraud- 
ing any  particular  person  or  persons,  or  the  public,  or  persons 
generally,  shall  be  deemed  guilty  of  a  felony,  and  on  conviction 
thereof  shall  be  punished  b}-  imprisonment  in  State  prison,  or 
a  county  jail,  not  exceeding  two  years,  or  by  fine  not  exceeding 
five  thousand  dollars,  or  by  both. 

Sec.  2.  All  Acts  and  parts  of  Acts  in  conflict  with  this  Act 
are  hereby  repealed. 

Approved  March  22,  1905. 


INDEX. 


Page. 
Abbott  mine 46 

Adelaide  district 150 

Alice  and  Modoc  mine 154 

vEtna  Consolidated  mines _     7J 

Alta  .- no 

Alloona  mine 192 

Baker  mine 49 

Bitujneu  in  cinnabar  ore  deposits 

25,  41,47,  161 

Boston  mine "6 

Central  San  Benito  mining  district    _.  125 

Cerro  Bonito  mine 134 

Chertbeds - 17 

Chert  beds  and  ore  deposits 54,  99 

Clear  Lake  district -     39 

Cloverdale  mine 98 

Colusa  County,  Mines  in  : 

Central ..   .      43 

Elgin     43 

Empire - 43 

Manzanita 44 

Wide  Awake 45 

Concentration  of  quicksilver  ores 198 

Concentration  plant,  Cost  of 202 

Condensation  of  the  furnace  fumes...  234 

Condensers,  Brick  __ 249 

Products  ._ 239 

Waterbacks.. 251 

Watertank 251 

Wooden _ 252 

Condensing-box,  Boston  mine 202 

Condensing,  Principles  of.. 243 

Contra  Costa  County,  Cinnabar  in 195 

Corona  mine  7'J 

Cost  of  mining  and  reduction 

34,201,208,214 

Cost  of  timber  and  wood 

3><,  39,  42,  129,  130,  153,  186 

Cretaceous  formations 16 

Culver-Bacr  mine 102 

Del  Norte  County,  Mines  in .     .  195 

Draft   in  furnace   plant.      (See   "  Fur- 
naces.") 

Dry-bone 37 

Elevations 254 

El  Dorado  County,  Mine  in 190 

Eureka  mine .  ..    106 

Franciscan  series  .    12 

Fresno  County,  Mines  in  : 

Arrambide  and  Aurecoechea 119 

Mexican 119 

Providential  group 121 


Furnaces :  Page. 

Data  regarding  tile  furnaces 223 

Discharging  methods 235 

Exeli,  continuous 208 

Fitzgerald.   205 

General  arrangement  of  plant....  234 

Hiittner-Scott 218 

Knox  &  Osborne  coarse-ore 210 

Knox  &  Orborne  fine-ore 215 

Litchfield  .- 215 

Livermore 215 

Luckhardt _  210 

Ore-drying  systems 225 

Material  for 206,  224 

Neat's 210 

New  Idria  coarse-ore 213 

Products  of  combustion  of 198 

Requirements  of 205 

Retort.     (See  "Retort  Furnace.") 

Temperature  in... 234 

Tiles 221 

Furnace  fumes.  Composition  of_   239 

Furnace  plant,  Draft  in 240 

Gas  in  the  mines 65.  110 

Geological    table    of    the    Cretaceous 

period       __ 16 

Geology  of  the  quicksilver  belt  in  Cali- 
fornia..  _. 12 

Granite,  Description  of 14 

Granite,  Its  occurrences  in  the  Coast 

Ranges . _ 12 

Great    Eastern    and    Mount    Jackson 

mines  ._ 108 

Great  Western  mine 52 

Guadalupe  mine 173 

Heat,     Increase    with     depth    under- 
ground  - ---     70 

Helen  (American)  mine 55 

Igneous  rocks.  21,  39,  129,  149,  152,  163 

Igneous  rocks  and  ore  deposition. ..21,  28, 

36.  .58,  62,  71,  77, 81,  91,  130,  148,  156,  191,  194 

Integral  mine 193 

Karl  mine 157 

Kings  County,  Mines  in 122 

Knoxville  district.. 42 

Lake  County,  Mines  in  : 

Abbott    46 

.Anderson  48 

Baker 49 

Big  Injun  (New  Phoenix  Mining 

Co.) 50 

Chicago  (Ural) 51 


979 


INDEX. 


Lake  County.  Mines  in  :  Page. 

Digger    Injun    (Congress    Mining 

Co) 50 

Great  Western  _   52 

Helen  (American) o.i 

Jewess 57 

Kingof  All  57 

Lucitta 5S 

Middletown .59 

Shamrock     ._  60 

Standard     Quicksilver     Company 

(Mirabeland  Bullion) 60 

Sulphur  Bank 61 

Thorn 70 

Utopia 70 

Wall  Street 71 

La  Libertad  mine 159 

Little  Panoche  mining  district 119 

Lucitta  mine 58 

Madrone  mine..  161 

Mahoney  (Buena  Vista  or  Gould)  mine  161 

Manhattan  mine 81 

Manzanita  mine 44 

Mariposa  County,  Cinnabar  ore  in 195 

Mayacmas  district 35 

Metacinnabarite 25,  31 

Metacinnabarite,  its  occurrence 

..47,49,79,  124,160,166 

Mercury  and  heat 29 

Mercury,  Occurrence  of  native 31 

(See,  also,  ''Native  Mercury.") 

Metallurgy- 197 

Metamorphic  series.  Age  of  . 12 

Xon-conformitj' with  theChico...  128 
Metamorphism  of  the  older  series  in 

the  Coast  Range 19 

Mining  timbers,  Protection  of 143 

Mist-loss.. 239,244 

Monterey  County.  Mines  in : 

Cholame-Parkfield.. 123 

Dutro 12-1 

Table  Mountain 124 

Mudrock... 82 

Xapa  Countj",  Mines  in : 

-Etna  Consolidated 72 

Bella  Union.. 76 

Boston 76 

Corona.  —     79 

Lajoya 80 

Manhattan 

Northern  Light 9 

Oathill...   -    SO 

Philadelphia 92 

Red  Elephant 92 

Summit _ 92 

Twin  Peaks 92 

Xati ve  mercurj- 32, 115, 110 

Xeocomian  series 12 

Xew.Almaden  mine 174 

New  Idria  district _ 125 

Xevi-  Idria  mine —  138 


Page. 

Oathill  (Xapa  Consolidated)  mine 89 

Oceanic  district 151 

Oceanic  mine 162 

Pine  Mountain  district 152 

Pine  Mountain  mine 163 

Polar  Star  mine 165 

Pre-Cretaceous  series 12 

Price  of  quicksilver  (annual  since  1S50)    10 
Production     of    quicksilver    (Annual 

since  ia50) ..     30 

Production  of  quicksilver  at  Xew  Al- 

raaden  . 176 

Quicksilver  ores  and  antimony  ores...  148 

.\ud  chalcedony 85 

.^nd  cherts 54,  99 

-■ind  copper    14S 

.■\nd  gold  ores 44 

And  Igneous  Rocks.     (See  "Igne- 
ous Rocks") 
And     Sandstone.        'See     "Sand- 
stone.") 
And   Serpentine.       (See   "Serpen- 
tine ") 

Description 24 

Genesis  of 26 

Formed  by  solution  and  precipita- 
tion  30,65,171 

Formed  by  sublimation 30 

Forming  at  the  present  time 45,  65 

Quicksilver  rock   20 

Ramirez  Consolidated  (Las  Picachos) 

inines 145 

Retort  furnaces 197.  203 

Cost  of._ 202,205 

Johnson  &  McKay 202 

G.  V.  Xorthey 200 

San  Benito  County,  Geologj-  of 125 

San  Benito  Countj-,  Mines  in  : 

.\ndj-  Johnson 131 

Aurora    131 

Bradford 131 

Boston.    (See  "  Clear  Creek.") 

Butts   133 

Cannon 133 

Cerro  Bonito 134 

Clear  Creek 137 

Don  Juan  and  Don  Miguel 137 

Fourth  of  July 138 

Mariposa — 138 

Xew  Idria        l'>8 

Philadelphia  and  Xew  York 145 

Ramirez  Consolidated  (Los  Pica- 
chos)   145 

San  Carlos  _ U3 

Santa  Cruz 147 

Stayton 147 

San  Carpojo  district 15! 

Sandstones 17,  93,  r21,  1'2C,  13.5 

Sandstones  and  ore  deposits 

91,95,  104,  119,121,  138.  141,  161,163 


INDEX. 


273 


Page. 
San  Luis  Obispo  County,  Geology  of..  149 
San  Luis  Obispo  County,  Mines  in: 

Alice  and  Modoc 154 

Bank  mine 154 

Cypress  Mountain 156 

Doty 156 

Elizabeth 157 

Eureka 157 

George  and  Josephine. 157 

Karl .     157 

Kismet 159 

La  Libertad 159 

Lehman. 101 

Madrone _   .   161 

Mahoney  (Buena  Vista  or  Gouldj..  161 

North  Star  _  162 

Oceanic 162 

Oceanic  No.  2 163 

Pine  Mountain  ..   163 

Polar  Star 165 

Quien  Sabe 165 

Rincouada 166 

Sunset  View  . 167 

Vulture  .- 167 

William  Tell 168 

Wittenberg _ 168 

Santa  Barbara  County,  Mines  in. 196 

Santa  Clara  County,  Geology  of. 168 

Santa  Clara  County,  Mines  in  : 

Bernal 171 

Comstock 172 

Costello 172 

Guadalupe 173 

Hillsdale 174 

New  Almaden 174 

Santa  Teresa.. 186 

Silver  Creek 187 

Wright- - 1S7 

Santa  Teresa  mine.. 186 

Serpentine,  Its  derivation 13,  33,  127 

Serpentine,  Relation  to  cinnabar  de- 
posits   36,46, 

75,    76,    88,    104,    106,    108,    114,    132,   142, 
144,   149,   154,   157,   160,   166,   168,   178,  190 

Serpentine,  Surface  occurrences 

74,  119,123,187 

Silicification  and  cinnabar  deposits...     33 

Silicifications  process 19,  180 

SiU-er  Creek  mine 187 

Siskiyou  County,  Mines  in 196 

Socrates  mine 115 

Solano  County,  Mine  in— St.  John  ...     93 
Sonoma  County,  Mines  in  : 

Almaden,  etc. 97 

Bacon  Consolidated 97 

Boston 97 

Cinnabar  King 98 


Sonoma  County,  Mines  in  :  Page. 

Cloverdale 98 

Clyde   _ 102 

Crown  Point. 102 

Crystal.    (See  "  Pacific") 

Culver-Baer 102 

Double  Star 105 

Eureka 106 

Great  Eastern 108 

Great  Northern 112 

Hope 112 

Hurley 112 

Lookout 113 

Lucky  Stone '. 113 

Maricoma 113 

Mercury  Mining  Co 113 

Missouri _ 113 

Mount      Jackson.       (See      "Great 
Eastern.") 

Napa 113 

Oakland.     (See  "Culver-Baer.) 

Occidental  and  Healdsburg 114 

Old  Chapman.- 114 

Pacific 114 

Pontiac 115 

Rattlesnake ....   .   115 

Socrates 115 

Sonoma.    (See  "Crown  Point.") 

Walker 116 

Wall  Springs ..  117 

Soot 239,214,253 

Standard  Quicksilver  Co.  (Mirabel)...     60 
Stanislaus  County,  Mines  in  : 

.\dobe  Valley 189 

Orestemba 189 

Summit 188 

Stayton  district.. 129 

Stay  ton  mine 147 

St.  John  mine... 93 

Sulphur  Bank  mine 61 

Sulphur  Creek  district. 40 

Summit  group 188 

Trinity  County,  Geology  of 190 

Trinity  County,  Mines  in  : 

Altoona 192 

Carr 193 

Integral 193 

Trinity 195 

Tuffoid 41 

Twin  Peaks  mine.. 92 

Water,  Underground  circulation 28 

Waters.  Composition  of  underground.    66 
Yolo  County.  Mines  in  : 

New  England  and  Harrison 117 

Reed :  117 

Royal 117 

Zones  of  the  earth  crust  26 


s  ^^6  3 

J 


UCD  LIBRARY 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 


BOOKS  REQUESTED  BY  ANOTHER  BORROWER 
ARE  SUBJECT  TO  IMMEDIATE  RECALL 


juNsoaooo 

m  2  8  2000  HE  J 


^    PSL 


MAR  0  3  2C03 
H,irCEiVEU 

MAR  1  h  2u03 
PSL 

JUL  0"S  '2005 


L^^feJvPS^K^bF  CALIFORNIA,   DAVIS 

http://libnte.ucdavis.edu/PatronRenew.html 

Automated  Phone  Renewal  (24-hour):  (530)  752-1132 

D4613  (4/99)M 


